所有大鼠均按照首都医科大学附属北京友谊医院动物实验委员会批准的方案使用。
1. 手术准备、麻醉和手术技术
注意:本研究共获得40只雌性Wistar大鼠，重200-220克。在40只大鼠中，随机选择10只作为对照组，其余作为试验组。所有动物均在首都医科大学附属北京友谊医院动物设施的无菌环境中饲养。
<ol><li>通过腹腔注射戊巴比妥钠（40mg / kg）进行全身麻醉。或者，使用3%-4%异氟醚诱导麻醉并将其维持在1%-3%（吸入）。在眼睛上涂抹眼药膏以防止干燥。然后，将大鼠放在手术平台上并提供热支持。 注意:在程序开始时给予镇痛药，如丁丙诺啡，0.05 mg / kg，SC，0.1-0.2 mL。</li>
	<li>检查麻醉深度是否对脚趾捏没有反应。用剃须刀剃掉整个背部区域的皮毛。</li>
	<li>用至少 3 个周期的两阶段擦洗（如洗必泰或聚维酮碘）对手术部位进行消毒，然后使用异丙醇。用手术胶带固定四肢，并用手术剪刀在背部做一个约3厘米的正中切口。</li>
	<li>使用手术剪刀加深皮下组织的切口，并切断附着在脊柱上的肌肉。</li>
	<li>目视识别并暴露第 13根 肋骨（连接到该肋骨的椎间空间为间隔 T13\u2012L1）。用缝合线标记第 13 根肋骨。</li>
	<li>识别后，小心地切除附着在脊柱上的肌肉并暴露椎体。切除棘上韧带和棘间韧带，以准确识别脊柱。用手术剪刀和镊子暴露L4-5的水平。 注意:由于存在薄的皮下组织，可以轻松识别棘上韧带。棘上韧带切除后，棘突之间的韧带为棘间韧带。</li>
	<li>使用凯利镊子仔细解剖L4\u2012L5椎棘突和部分横向突，露出脊髓（图1）。</li>
	<li>在L4-l5水平完全暴露髓圆锥，并用虹膜切除剪刀完全横断髓圆锥。插入一些组织包装以阻止脊髓的恢复。</li>
	<li>使用4-0不可吸收缝合线关闭外层皮肤上的覆盖肌肉和皮肤。</li>
	<li>对于对照组，执行步骤 1.1-u20121.7，并保持髓圆锥完整。按照步骤1.9关闭切口。</li>
</ol>2. 动物恢复
<ol><li>在手术后的第一个小时内将大鼠保持在温控培养箱（37°C）中，并监测它们直到它们胸骨或积极移动。 注意:完全恢复大约需要半小时。</li>
	<li>将动物转移到装有足够食物和水的干净笼子中。将老鼠放在单独的笼子里。 注意:当测试组中的大鼠仅在前腿的帮助下移动时，表明横断的成功，而对照组中的大鼠可以正常行走。</li>
</ol>3. 后期运营管理
<ol><li>腹腔注射青霉素G，一种抗生素（每只动物50，000U / mL）。术后48小时每6-12小时给予丁丙诺啡，0.05mg / kg，SC，0.1-0.2mL等镇痛药。</li>
	<li>在下胃压迫膀胱以帮助排尿。每天在同一时间（上午 8 点和晚上 8 点）执行此操作两次，持续六周。 注意:逼尿肌正常收缩的丧失是DU的标志。</li>
	<li>将所有大鼠安置在代谢笼中，每只大鼠都包含一个尿液收集漏斗，放置在先前称重的吸收纸上以监测排尿和尿失禁。</li>
	<li>收集并注意吸收纸的重量变化，分别指示排尿量（VV）和残余尿量。</li>
</ol>4. 尿动力学检查
<ol><li>在手术后六周，使用尿动力学测量设备进行膀胱测量图，如下所示。<ol><li>通过将10%水合氯醛注射到腹膜腔（3mL / kg）来麻醉大鼠。</li>
		<li>压缩膀胱排尿，然后使用胶带将大鼠固定在手术平台上。</li>
		<li>将硬膜外导管（3F）插入膀胱，并通过三肢管连接尿动力学测量设备，硬膜外导管和输液泵。</li>
		<li>以0.2mL / min的速度泵送生理盐水以进行尿动力学测量（见 材料表）。记录MCC和DOP以及膀胱的顺应性（通过将膀胱体积除以逼尿肌的压力δ δ计算）。</li>
	</ol></li>
</ol>5. 统计分析
<ol><li>使用市售软件执行统计分析。</li>
	<li>使用柯尔莫哥罗夫-斯米尔诺夫检验来检验数据的正态性。</li>
	<li>将正态分布变量表示为具有标准差的平均值。使用双尾配对学生 t 检验来比较两组膀胱测量图的参数。 注: p < 0.05表示差值具有统计学意义。</li>
</ol>

<ol>
	<li>van Koeveeringe, G. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detrusor+underactivity:+Pathophysiological+considerations,+models+and+proposals+for+future+research.">Detrusor underactivity: Pathophysiological considerations, models and proposals for future research.</a> Neurourology and Urodynamics. 33 (5), 591-596 (2014).</li><li>Osman, N. I., Esperto, F., Chapple, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detrusor+Underactivity+and+the+Underactive+Bladder:+A+Systematic+Review+of+Preclinical+and+Clinical+Studies.">Detrusor Underactivity and the Underactive Bladder: A Systematic Review of Preclinical and Clinical Studies.</a> European Urology. 74 (5), 633-643 (2018).</li><li>Osman, N. I., Chapple, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contemporary+concepts+in+the+aetiopathogenesis+of+detrusor+underactivity.">Contemporary concepts in the aetiopathogenesis of detrusor underactivity.</a> Nature Reviews. Urology. 11 (11), 639-648 (2014).</li><li>Panicker, J. N., Nagaraja, D., Kovoor, J. M. E., Nair, K. P. S., Subbakrishna, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lower+urinary+tract+dysfunction+in+acute+disseminated+encephalomyelitis.">Lower urinary tract dysfunction in acute disseminated encephalomyelitis.</a> Multiple Sclerosis. 15 (9), 1118-1122 (2009).</li><li>Lee, W. C., Wu, H. P., Tai, T. Y., Yu, H. J., Chiang, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+urodynamic+characteristics+and+bladder+sensory+function+in+the+early+stages+of+diabetic+bladder+dysfunction+in+women+with+type+2+diabetes.">Investigation of urodynamic characteristics and bladder sensory function in the early stages of diabetic bladder dysfunction in women with type 2 diabetes.</a> The Journal of Urology. 181 (1), 198-203 (2009).</li><li>Araki, I., Kitachara, M., Oida, T., Kuno, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Voiding+dysfunction+and+Parkinson’s+disease:+urodynamic+abnormalities+and+urinary+symptoms.">Voiding dysfunction and Parkinson’s disease: urodynamic abnormalities and urinary symptoms.</a> The Journal of Urology. 164 (5), 1640-1643 (2000).</li><li>Meng, N. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Incomplete+bladder+emptying+in+patients+with+stroke:+is+detrusor+external+sphincter+dyssynergia+a+potential+cause.">Incomplete bladder emptying in patients with stroke: is detrusor external sphincter dyssynergia a potential cause.</a> Archives of Physical Medicine and Rehabilitation. 91 (7), 1105-1109 (2010).</li><li>FitzGerald, M. P., Brubaker, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+etiology+of+urinary+retention+after+surgery+for+genuine+stress+incontinence.">The etiology of urinary retention after surgery for genuine stress incontinence.</a> Neurourology and Urodynamics. 20 (1), 13-21 (2001).</li><li>Rahman, M., Siddik, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuroanatomy,+Pontine+Micturition+Center.">Neuroanatomy, Pontine Micturition Center.</a> StatPearls. , (2020).</li><li>Wrobel, A., Lancut, M., Rechberger, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+model+of+detrusor+overactivity+in+conscious+rats+induced+by+retinyl+acetate+instillation.">A new model of detrusor overactivity in conscious rats induced by retinyl acetate instillation.</a> Journal of Pharmacological and Toxicological Methods. 74 (7), 16 (2015).</li><li>Rosenzweig, E. S., McDonald, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rodent+models+for+treatment+of+spinal+cord+injury:+research+trends+and+progress+toward+useful+repair.">Rodent models for treatment of spinal cord injury: research trends and progress toward useful repair.</a> Current Opinion in Neurology. 17 (2), 121-131 (2004).</li><li>Yoo, K. H., Lee, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+animal+models+of+neurogenic+bladder+dysfunction.">Experimental animal models of neurogenic bladder dysfunction.</a> International Neurourology Journal. 14 (1), 1-6 (2010).</li><li>Kanai, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sophisticated+models+and+methods+for+studying+neurogenic+bladder+dysfunction.">Sophisticated models and methods for studying neurogenic bladder dysfunction.</a> Neurourology and Urodynamics. 30 (5), 658-667 (2011).</li><li>Nomiya, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Progressive+vascular+damage+may+lead+to+bladder+underactivity+in+rats.">Progressive vascular damage may lead to bladder underactivity in rats.</a> The Journal of Urology. 191 (5), 1462-1469 (2014).</li><li>Seki, T., Hida, K., Tada, M., Koyanagi, I., Iwasaki, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Graded+contusion+model+of+the+mouse+spinal+cord+using+a+pneumatic+impact+device.">Graded contusion model of the mouse spinal cord using a pneumatic impact device.</a> Neurosurgery. 50 (5), 1075-1081 (2002).</li><li>Yeo, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+rat+model+of+graded+contusive+spinal+cord+injury+using+a+pneumatic+impact+device.">Development of a rat model of graded contusive spinal cord injury using a pneumatic impact device.</a> Journal of Korean Medical Science. 19 (4), 574-580 (2004).</li><li>Bergman, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spinal+cord+transplants+permit+the+growth+of+serotonergic+axons+across+the+site+of+neonatal+spinal+cord+transection.">Spinal cord transplants permit the growth of serotonergic axons across the site of neonatal spinal cord transection.</a> Brain Research. 431 (2), 265-279 (1987).</li><li>Chancellor, M. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Underactive+bladder;+Review+of+progress+and+impact+from+the+International+CURE-UAB+Initiative.">Underactive bladder; Review of progress and impact from the International CURE-UAB Initiative.</a> International Neurourology Journal. 24 (1), 3-11 (2020).</li><li>Pfisterer, M. H. D., Griffiths, D. J., Schaefer, W., Resnick, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+age+on+lower+urinary+tract+function:+a+study+in+women.">The effect of age on lower urinary tract function: a study in women.</a> Journal of the American Geriatrics Society. 54 (3), 405-412 (2006).</li><li>Duchen, L. W., Anjorin, A., Watkins, P. J., Mackay, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathology+of+autonomic+neuropathy+in+diabetes+mellitus.">Pathology of autonomic neuropathy in diabetes mellitus.</a> Annals of Internal Medicine. 92 (2), 301-303 (1980).</li><li>Schneider, T., Hein, P., Bai, J., Michel, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+role+for+muscarinic+receptors+or+rho-kinase+in+hypertension+associated+rat+bladder+dysfunction.">A role for muscarinic receptors or rho-kinase in hypertension associated rat bladder dysfunction.</a> The Journal of Urologoy. 173 (6), 2178-2181 (2005).</li><li>Drake, M. J., Harvey, I. J., Gillespie, J. I., Van Duyl, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Localized+contractions+in+the+normal+human+bladder+and+in+urinary+urgency.">Localized contractions in the normal human bladder and in urinary urgency.</a> BJU International. 95 (7), 1002-1005 (2005).</li><li>Suskind, A. M., Smith, P. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+look+at+detrusor+underactivity:+impaired+contractility+versus+afferent+dysfunction.">A new look at detrusor underactivity: impaired contractility versus afferent dysfunction.</a> Current Urology Reports. 10 (5), 347-351 (2009).</li><li>Osman, N. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detrusor+underactivity+and+the+underactive+bladder:+A+new+clinical+entity?+A+review+of+current+terminology,+definitions,+epidemiology,+aetiology,+and+diagnosis.">Detrusor underactivity and the underactive bladder: A new clinical entity? A review of current terminology, definitions, epidemiology, aetiology, and diagnosis.</a> European Urology. 65 (2), 389-398 (2014).</li></ol>

作者没有什么可透露的。

贫铀是男性和女性下尿路症状的常见原因。这是一个复杂的症状群，几乎没有治疗选择，可以显着降低受影响者的生活质量（Qol）18。尽管人们认为贫铀是多因素的，但对其发病机制的理解仍然很初步。研究表明，贫铀的发病机制可能与肌源性和神经源性因素有关。
在肌源性假说中，观察到患有贫铀的人可能比健康衰老的人经历更显着的逼尿肌收缩力下降。研究发现，逼尿肌收缩力随着年龄的增长而减弱，并且可能受到代谢或神经源性疾病等其他因素的影响。尿动力学评估数据显示，贫铀和排尿后残留与衰老有关19.一项研究表明，22.1% 的男性和 10.8% 的女性（年龄均> 60 岁）报告膀胱排空困难3.此外，这背后的主要原因是逼尿肌收缩力降低。对糖尿病膀胱的研究显示出与DU20中发现的类似的变化。肌肉与胶原蛋白比例的降低导致肌肉细胞之间的空间扩大可能导致逼尿肌收缩力降低。在大多数神经源性膀胱中也发现与年龄相关的循环去甲肾上腺素增加21，22。因此，已经有人尝试通过在动物模型中建立糖尿病来诱导贫铀。但由于缺乏对血糖水平和糖尿病其他并发症的准确控制，这些都失败了。然而，在神经源性假说中，DU被分为三组:排尿反射传出信号中的障碍，启动反射的传入信号的障碍和有缺陷的综合控制23。因此，许多研究人员注意通过神经源性系统成分的准确损伤来建立动物模型。由于神经源性系统的复杂功能，很难确定诱导贫铀的位置。 不幸的是，许多利用神经源性系统损伤来诱导贫铀的尝试都失败了。
我们的协议是通过横断髓圆锥建立贫铀动物模型的第一份报告。在本研究中，脊髓在L4\u2012L5水平上横断，以诱导下骶神经损伤。
手术最关键的一步是在L4\u2012L5水平上识别脊髓，因为大鼠的圆锥髓质又长又细，范围从L1的上侧到L4的下侧。如果脊髓横断在L4上方，则可能会诱发骶上神经损伤。相反，如果横断发生在L5以下，则可能无法根除排尿中心。因此，在L4-L5水平上进行横断手术可以确保排尿中心的传入和传出通路都被破坏，这使得这种方法独一无二。
在试验组中，手术后立即出现尿潴留，残余尿量的变化曲线对应于脊髓损伤休克期期间或之后排尿功能的变化。同时，未观察到经典反射性尿失禁余震阶段，表明膀胱传出神经受损。
我们还发现手术后第一周残余尿液增加，第一周后残留尿液显着减少。残余尿液的变化可能是由出口/括约肌/盆底功能协调受损引起的。因此，在手术后的第一周，突然的破坏导致残余尿液增加，当出口/括约肌/盆底功能的损害在一定程度上重建时，残留尿液下降到稳定水平。
根据ICS设想的贫铀的含义:（1）逼尿肌收缩力太弱，（2）逼尿肌收缩跨度太短，它与膀胱排空不足（排尿效果降低），感觉减退和下尿路症状有关。在比较两组的尿动力学数据后，我们发现最大膀胱测量能力和测试组膀胱的顺应性在术后6周显着增加，而逼尿肌开放压力降低。在这些数据的帮助下，很明显，逼尿肌的收缩力在六周后下降，导致膀胱无法收缩以诱导排尿。
如膀胱压力 - 体积曲线所示，随着最大膀胱容量的增加，排尿没有出现，尽管逼尿肌的压力也被夸大了。没有排尿表明手术通过引起膀胱传入神经排尿障碍来阻断诱导排尿的传入信号。此外，这些特征与DU的病理生理变化相对应。
这项研究也有局限性。例如，应采取重症监护以防止手术后感染。根据我们的经验，髓圆锥横断可能导致下后肢动力受损。此外，滞留尿液的泄漏（由于尿失禁）可能很难快速发现，导致尿液润湿的潮湿笼床与动物下半身之间的持续接触。这可能导致严重的皮肤或尿路感染，这可能是致命的。该协议要求显微外科经验有限的外科医生接受广泛的外科培训以掌握该技术，尤其是髓圆锥的准确识别。
由于膀胱排空受阻的临床症状（例如，尿流速降低、排尿后残余 [PVR] 升高）可能因 DU 而出现，但同样也可能因膀胱流出道梗阻 （BOO）（例如良性前列腺增生、尿道狭窄）而发生。因此，需要定期测试以识别DU和BOO，而无需进行侵入性压力流量研究24 。然而，在我们的模型中，在由逼尿肌收缩能力受损引起的尿动力学测试中没有观察到排尿。同时分析BOO因子具有挑战性，这也是模型的局限性。
综上所述，通过截断圆锥髓质建立贫铀动物模型，为进一步了解贫铀提供了一个理想的动物模型。通过适当的培训和实践，这种手术的成功率可以超过95%。

逼尿肌活动不足（DU）是一种典型的下尿路功能障碍，至今仍在研究中。尽管贫铀已由国际尿失禁协会（ICS）1定义，但使用许多不同的术语来指代这种疾病，例如"逼尿肌衰竭"、"收缩性膀胱"、"逼尿肌反射消失"2。根据国际尿失禁协会 （ICS） 在 2002 年的定义，DU 是一种力量和持续时间减少的收缩，导致膀胱排空时间延长，从而导致无法在正常时间内实现膀胱完全排空。
DU 可能影响 48% 的男性和 12% 的女性（>70 岁）3 伴有下尿路症状。它似乎是多因素的，并且没有有效的治疗方法。据悉，DU在神经源性膀胱功能障碍患者中普遍存在，如多发性硬化症4、糖尿病5、帕金森病6或脑卒中7。贫铀也可由医源性神经损伤引起，例如腹腔镜子宫切除术、前列腺切除术或其他小骨盆的手术干预8.由于缺乏合适的动物模型进行研究，贫铀的病理生理学变化和可用的治疗方法仍然令人困惑。
排尿反射由脊柱-球脊髓通路控制，该通路结合了脑桥排尿中心、骶副交感神经核和更高级的皮质中心9。排尿反射的激活和维持主要取决于感觉信号从膀胱到更高级的皮层中心的定期传输。可以推测感觉功能障碍会导致 DU。
大多数与下尿路功能障碍相关的实验动物研究都集中在膀胱过度活动症（OAB）模型10上。这些模型提供了对OAB病理生理学和预后的合理理解。然而，只有少数 DU 模型被报道，例如脊髓上损伤（局部病变、去脑和大脑中动脉闭塞）、脊髓横断或挫伤、全身性（例如环磷酰胺）或膀胱内给予刺激性或炎症性物质（例如酸、丙烯醛和脂多糖）11，12，13，14.在这些方法中，只有脊髓横断或挫伤法可用于建立DU13的动物模型。由于严重的创伤，涉及脑桥排尿中心和高级皮层中心损伤的尝试被放弃。因此，人们越来越注意在排尿反射中心找到一个准确的位置，以最小的副作用诱导贫铀。
如前所述，诱导贫铀的机制之一是损伤脊髓以损害排尿反射的信号通路。艾伦的减重方法是为了建立脊髓受伤的实验动物而开发的15。但是，没有关于该方法的进一步实验数据。此外，由于部分动物在没有DU的情况下恢复了中风后的脊柱功能，因此不能将其视为生成DU动物模型16的完美方法。
1987年，布雷格曼发现了一种横断脊髓的过程，以生成DU动物模型，并获得了实验数据17。然而，该方法并未应用于建立贫铀动物模型。当时，研究人员仍然对DU的发病机制感到困惑。由于脊髓中与OAB或DU诱导相关的位置彼此相邻，因此他们无法找到脊髓损伤的准确位置以诱导DU17。OAB和DU要么一起引入，要么通过这种方法单独引入。因此，这种方法虽然引入了DU，但它并不精确，不能用于理解DU的发生和处理。
如上所述，缺乏合适的贫铀动物模型是贫铀研究的主要障碍之一。 研究人员一直在寻找一种准确且可管理的模型，可以模拟贫铀的病理学。在过去20年中，即使是贫铀的治疗方案也没有显著改善。总的来说，非常需要描述建立DU动物模型的标准协议。
因此，在本文中，我们描述了一种通过圆锥髓质横断成功建立DU大鼠模型的方法。在L4-L5水平进行横断，以分离髓圆锥。记录并分析膀胱的最大膀胱容量（MCC），逼尿肌开口压力（DOP）和膀胱顺应性以验证方案。下面所述的协议以标准化的方式结合了可行性和可靠性，以建立贫铀动物模型，模拟贫铀的发生和处理。该协议可用作进一步研究DU的技术。

<table>
	<tbody>
		<tr>
			<td>0.9% saline</td>
			<td>Wuhan Prosai Company</td>
			<td>EY-C1178</td>
			<td>pump for urodynamic measurement</td>
		</tr>
		<tr>
			<td>10% chloral hydrate</td>
			<td>Shandong Yulong Co., Ltd</td>
			<td>H37022673</td>
			<td>3mL/kg&#65292;administered intraperitoneally</td>
		</tr>
		<tr>
			<td>Buprenorphine Hydrochloride Injection</td>
			<td>Tianjin Pharmaceutical Research Institute Pharmaceutical Co. LTD</td>
			<td>H12020275</td>
			<td>0.05mg/kg subcutaneously 24h and 48h postoperation</td>
		</tr>
		<tr>
			<td>Epidural Catheter</td>
			<td>Shandong Xinghua Co, Ltd</td>
			<td>VABR3L</td>
			<td>for urodynamic measurement</td>
		</tr>
		<tr>
			<td>Penicillin G</td>
			<td>Alta Technology Co., Ltd</td>
			<td>1ST5637</td>
			<td>50,000 unit/ml per animal</td>
		</tr>
		<tr>
			<td>pentobarbital</td>
			<td>Beijing solabo Technology Co., Ltd</td>
			<td>NK-WF0001</td>
			<td>40 mg/kg, administered intraperitoneally</td>
		</tr>
		<tr>
			<td>Suture line(4-0)</td>
			<td>ETHICON</td>
			<td>VCP422H</td>
			<td>suture the injury</td>
		</tr>
		<tr>
			<td>Three-limb tube</td>
			<td>Shandong Xinghua Co, Ltd</td>
			<td>VAB3T</td>
			<td>for urodynamic measurement</td>
		</tr>
		<tr>
			<td>Trace infusion pump</td>
			<td>Zhejiang Smith Medical Instrument Co., Ltd</td>
			<td>20162540335</td>
			<td>Pump the saline at a speed of 0.2ml/min for urodynamic measurement</td>
		</tr>
		<tr>
			<td>Urodynamic measurement equipment</td>
			<td>Medical Measurement SystemsB.V.</td>
			<td>08-0467</td>
			<td>urodynamic measurement equipment can not only help the diagnosis of dysuria, but also provide objective materials for treatment and therapeutic effect. It is the most commonly used examination method in clinical diagnosis and treatment of lower urinary tract functional diseases</td>
		</tr>
		<tr>
			<td>Wistar Rats</td>
			<td>HFK Biotechnology Co.Ltd,Beijing ,China</td>
			<td>SCXK2012-0023</td>
			<td>200-220g</td>
		</tr>
	</tbody>
</table>

detrusor underactivity model in rats by conus medullaris transection

所提出的协议的目标是通过圆锥髓质横断在大鼠中建立逼尿肌活动不足（DU）模型。在总共40只雌性Wistar大鼠（对照组:10只大鼠;试验组:30只大鼠）中，体重200-220 g，在试验组中，髓圆锥在L4\u2012L5水平进行横断。将所有大鼠在相同的环境条件下饲养和喂养六周。在测试组中，每天进行两次排尿，持续六周，并记录平均残余尿量。两组均行膀胱测量图。记录并计算膀胱的最大膀胱测量容量（MCC），逼尿肌开放压力（DOP）和膀胱顺应性。测试组在手术后，无论是在脊柱休克期间还是之后，都显示出明显的尿潴留。但对照组未见异常。与对照组相比，试验组的MCC和膀胱顺应性显著高于试验组（3.24 ± 2.261 mL vs 1.04 ± 0.571 mL;0.43 ± 0.578 mL/cmH 2 O 对比 0.032 ± 0.016 mL/cmH 2 O），而试验组的DOP低于对照组（20.28 ± 14.022 cmH 2 O与35 ± 13.258 cmH22这种通过圆锥髓质横断建立贫铀动物模型的方法为更好地了解DU的病理生理学提供了绝佳的机会。

圆锥髓质横断的整个过程可以由经验丰富的外科医生在45分钟内完成。我们的实验室已经进行了100多例髓圆锥横断手术。成功率超过95%，由大鼠的存活率和成功诱导DU定义。尿动力学试验证实了DU的诱导。
根据我们的经验，贫铀的诱导可以通过残余尿量初步评估。手术后立即观察到尿液潴留。试验组术后第2天出现容量峰值点，体积下降逐渐持续10 d左右。手术后十天，体积达到稳定水平（图2）。观察到术后前10天，平均残余尿量为2.09±1.05mL，术后第10天降至 0.67±0.21mL。但对照组未见异常。
为了确认DU的诱导，需要进行尿动力学测试。测试组和对照组的代表性压力-体积曲线如图3和图4所示。与对照组相比，试验组的MCC和膀胱顺应性显著更高（分别为1.04 ± 0.571 mL vs. 3.24 ± 2.261 mL，p < 0.001和0.032 ± 0.016 mL/cmH 2 O和0.43 ± 0.578 mL/cmH 2 O，p < 0.05）显著降低，而试验组的DOP显著下降（35 ± 13.258 cmH 2 O与20.28 ± 14.022 cmH2O;p < 0.01）。请参阅表 1。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61576/61576fig01.jpg"> 图1:圆锥髓质横断的方法。 （a） 露出第13根肋骨（黑色箭头）。（b） 露出L4和L5椎弓。椎板被龙格破坏以揭开脊髓（黑色箭头）。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61576/61576fig01large.jpg" target="_blank">请点击此处查看此图的大图。</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/61576/61576fig02.jpg"> 图 2:测试组中排尿行为参数变化的时间过程。 值表示为平均值±标准偏差。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61576/61576fig02large.jpg" target="_blank">请单击此处查看此图的大图。</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/61576/61576fig03.jpg"> 图 3:测试组中具有代表性的膀胱测量痕迹。 （a） 对膀胱体积明显升高和逼尿肌压力低的大鼠的代表性追踪。（b） 从第二只大鼠进行代表性追踪，该大鼠表现出比平时更高的膀胱体积和略低的逼尿肌压力。在固定输液速度下，测试组的输液时间大不相同。然而，试验组所有大鼠的输注时间明显增加，这意味着膀胱增大。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61576/61576fig03large.jpg" target="_blank">请点击此处查看此图的大图。</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/61576/61576fig04.jpg"> 图 4:对照组中具有代表性的膀胱测量迹线。 （a）膀胱容量正常且输注后膀胱压力逐渐升高的大鼠。（b）膀胱容量正常且输注后膀胱压力逐渐升高的大鼠。在固定输注速度下，对照组中近6分钟的输注时间意味着对照组的膀胱体积相同。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/61576/61576fig04large.jpg" target="_blank">请点击此处查看此图的大图。</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always"><tbody><tr><td>群</td>
			<td>箱</td>
			<td>最大膀胱测量容量（毫升）</td>
			<td>逼尿肌开启压力（厘米高 2O）</td>
			<td>膀胱顺应性 （ml/H2O）</td>
		</tr><tr><td>测试组</td>
			<td>26</td>
			<td>3.24±2.261</td>
			<td>022±20.28</td>
			<td>0.43±0.578</td>
		</tr><tr><td>控制组</td>
			<td>10</td>
			<td>1.04±0.571</td>
			<td>35±13.258</td>
			<td>0.032±0.016</td>
		</tr><tr><td rowspan="2">T 值</td>
			<td rowspan="2"></td>
			<td>4.517</td>
			<td>-2.847</td>
			<td>3.435</td>
		</tr><tr><td>（p=0.000）</td>
			<td>（p=0.008）</td>
			<td>（p=0.002）</td>
		</tr><tr><td colspan="5">使用t检验进行统计分析。数据以平均±SD表示。</td>
		</tr><tr><td colspan="5">p<0.05被认为具有统计学意义。</td>
		</tr></tbody></table>表1:两组代表性的压力-体积曲线。

Watch this Scientific Journal Video about Detrusor Underactivity Model in Rats by Conus Medullaris Transection at JoVE.com

Detrusor Underactivity Model in Rats by Conus Medullaris Transection

我们提出了一种通过大鼠髓圆锥横断建立逼尿肌活动不足模型的方法。在这些动物中成功刺激了逼尿肌活动不足。该模型可用于研究尿路功能。

大鼠逼尿肌活动不足模型通过圆锥髓质横断

The goal of the presented protocol was to establish a detrusor underactivity (DU) model in the rat through conus medullaris transection. Laminectomy was ...

detrusor-underactivity-model-in-rats-by-conus-medullaris-transection

Nanyang Technological University

Research

JoVE Journal

Neuroscience

2.0K 次观看.  Capital Medical University. 我们提出了一种通过大鼠髓圆锥横断建立逼尿肌活动不足模型的方法。在这些动物中成功刺激了逼尿肌活动不足。该模型可用于研究尿路功能。

视频: Detrusor Underactivity Model in Rats by Conus Medullaris Transection

Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be accessed within the orbit of the eye and completely transected (axotomized), cutting the axons of the entire RGC population. Optic nerve 
transection is a reproducible model of apoptotic neuronal cell death in the adult CNS 1-4. This model is particularly attractive because the vitreous
 chamber of the eye acts as a capsule for drug delivery to the retina, permitting experimental manipulations via intraocular injections. The diffusion of chemicals 
through the vitreous fluid ensures that they act upon the entire RGC population. Moreover, RGCs can be selectively transfected by applying short interfering RNAs 
(siRNAs), plasmids, or viral vectors to the cut end of the optic nerve 5-7 or injecting vectors into their target, the superior colliculus 8. 
This allows researchers to study apoptotic mechanisms in the desired neuronal population without confounding effects on other bystander neurons or surrounding glia. 
An additional benefit is the ease and accuracy with which cell survival can be quantified after injury. The retina is a flat, layered tissue and RGCs are localized in 
the innermost layer, the ganglion cell layer. The survival of RGCs can be tracked over time by applying a fluorescent tracer (3% Fluorogold) to the cut end of the 
optic nerve at the time of axotomy, or by injecting the tracer into the superior colliculus (RGC target) one week prior to axotomy. The tracer is retrogradely transported, labeling 
the entire RGC population. Because the ganglion cell layer is a monolayer (one cell thick), RGC densities can be quantified in flat-mounted tissue, without the need 
for stereology. Optic nerve transection leads to the apoptotic death of 90% of injured RGCs within 14 days postaxotomy 9-11. RGC apoptosis has a 
characteristic time-course whereby cell death is delayed 3-4 days postaxotomy, after which the cells rapidly degenerate. This provides a time window for 
experimental manipulations directed against pathways involved in apoptosis.

Optic Nerve transection is a widely used model of adult CNS injury. Ninety percent of retinal ganglion cells (RGCs) whose axons are completely transected (axotomy) die within 14 days after axotomy. This model is easily amenable to experimental manipulations and highly reproducible.

视神经横断:一个成人在中枢神经系统的神经元凋亡模型

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be ...

科研

神经科学

Methods for Experimental Manipulations after Optic Nerve Transection in the Mammalian CNS

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. The optic nerve can be accessed within the orbit of the eye and completely transected (axotomized), cutting the axons of the entire RGC population. Optic nerve transection is a reproducible model of apoptotic neuronal cell death in the adult CNS 1-4. This model is particularly attractive because the vitreous chamber of the eye acts as a capsule for drug delivery to the retina, permitting experimental manipulations via intraocular injections. The diffusion of chemicals through the vitreous fluid ensures that they act upon the entire RGC population. Viral vectors, plasmids or short interfering RNAs (siRNAs) can also be delivered to the vitreous chamber in order to infect or transfect retinal cells 5-12. The high tropism of Adeno-Associated Virus (AAV) vectors is beneficial to target RGCs, with an infection rate approaching 90% of cells near the injection site 6, 7, 13-15. Moreover, RGCs can be selectively transfected by applying siRNAs, plasmids, or viral vectors to the cut end of the optic nerve 16-19 or injecting vectors into their target the superior colliculus 10. This allows researchers to study apoptotic mechanisms in the injured neuronal population without confounding effects on other bystander neurons or surrounding glia. RGC apoptosis has a characteristic time-course whereby cell death is delayed 3-4 days postaxotomy, after which the cells rapidly degenerate. This provides a window for experimental manipulations directed against pathways involved in apoptosis. Manipulations that directly target RGCs from the transected optic nerve stump are performed at the time of axotomy, immediately after cutting the nerve. In contrast, when substances are delivered via an intraocular route, they can be injected prior to surgery or within the first 3 days after surgery, preceding the initiation of apoptosis in axotomized RGCs. In the present article, we demonstrate several methods for experimental manipulations after optic nerve transection.

Optic Nerve transection is a widely used model of adult CNS injury. This model is ideal for performing a number of experimental manipulations that target the retina globally or directly target the injured neuronal population of retinal ganglion cells.

在哺乳动物的中枢神经系统视神经横断后的实验操作方法

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. The optic nerve can be ...

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural connectivity form during development. In mice, retinofugal projections are arranged in a topographic manner and form eye-specific layers in the Lateral Geniculate Nucleus (dLGN) of the thalamus and the Superior Colliculus (SC). The development of these precise patterns of retinofugal projections has typically been studied by labeling populations of RGCs with fluorescent dyes and tracers, such as horseradish peroxidase1-4. However, these methods are too coarse to provide insight into developmental changes in individual RGC axonal arbor morphology that are the basis of retinotopic map formation. They also do not allow for the genetic manipulation of RGCs.
Recently, electroporation has become an effective method for providing precise spatial and temporal control for delivery of charged molecules into the retina5-11. Current retinal electroporation protocols do not allow for genetic manipulation and tracing of retinofugal projections of a single or small cluster of RGCs in postnatal mice. It has been argued that postnatal in vivo electroporation is not a viable method for transfecting RGCs since the labeling efficiency is extremely low and hence requires targeting at embryonic ages when RGC progenitors are undergoing differentiation and proliferation6. 
In this video we describe an in vivo electroporation protocol for targeted delivery of genes, shRNA, and fluorescent dextrans to murine RGCs postnatally. This technique provides a cost effective, fast and relatively easy platform for efficient screening of candidate genes involved in several aspects of neural development including axon retraction, branching, lamination, regeneration and synapse formation at various stages of circuit development. In summary we describe here a valuable tool which will provide further insights into the molecular mechanisms underlying sensory map development.

Transfection of Mouse Retinal Ganglion Cells by in vivo Electroporation

We demonstrate an in vivo electroporation protocol for transfecting single or small clusters of retinal ganglion cells (RGCs) and other retinal cell types in postnatal mice over a wide range of ages. The ability to label and genetically manipulate postnatal RGCs in vivo is a powerful tool for developmental studies.

小鼠视网膜神经节细胞的转染在体内电穿孔

The targeting and refinement of RGC projections to the midbrain is a popular and powerful model system for studying how precise patterns of neural ...

A General Method for Evaluating Incubation of Sucrose Craving in Rats

For someone on a food-restricted diet, food craving in response to food-paired cues may serve as a key behavioral transition point between abstinence and relapse to food taking 1. Food craving conceptualized in this way is akin to drug craving in response to drug-paired cues. A rich literature has been developed around understanding the behavioral and neurobiological determinants of drug craving; we and others have been focusing recently on translating techniques from basic addiction research to better understand addiction-like behaviors related to food 2-4.
As done in previous studies of drug craving, we examine sucrose craving behavior by utilizing a rat model of relapse. In this model, rats self-administer either drug or food in sessions over several days. In a session, lever responding delivers the reward along with a tone+light stimulus. Craving behavior is then operationally defined as responding in a subsequent session where the reward is not available. Rats will reliably respond for the tone+light stimulus, likely due to its acquired conditioned reinforcing properties 5. This behavior is sometimes referred to as sucrose seeking or cue reactivity. In the present discussion we will use the term "sucrose craving" to subsume both of these constructs.
In the past decade, we have focused on how the length of time following reward self-administration influences reward craving. Interestingly, rats increase responding for the reward-paired cue over the course of several weeks of a period of forced-abstinence. This "incubation of craving" is observed in rats that have self-administered either food or drugs of abuse 4,6. This time-dependent increase in craving we have identified in the animal model may have great potential relevance to human drug and food addiction behaviors.
Here we present a protocol for assessing incubation of sucrose craving in rats. Variants of the procedure will be indicated where craving is assessed as responding for a discrete sucrose-paired cue following extinction of lever pressing within the sucrose self-administration context (Extinction without cues) or as responding for sucrose-paired cues in a general extinction context (Extinction with cues).

Responding for food or drug-paired cues increases over the course of a period of abstinence and this may relate to an increased susceptibility to relapse behaviors. Here we detail a procedure for evaluating this "incubation of craving" in rats that have self-administered sucrose.

评估大鼠蔗糖渴求育成的一个通用方法

For someone on a food-restricted diet, food craving in response to food-paired cues may serve as a key behavioral transition point between abstinence and ...

Generation of Topically Transgenic Rats by In utero Electroporation and In vivo Bioluminescence Screening

In utero electroporation (IUE) is a technique which allows genetic modification of cells in the brain for investigating neuronal development. So far, the use of IUE for investigating behavior or neuropathology in the adult brain has been limited by insufficient methods for monitoring of IUE transfection success by non-invasive techniques in postnatal animals. 
 For the present study, E16 rats were used for IUE. After intraventricular injection of the nucleic acids into the embryos, positioning of the tweezer electrodes was critical for targeting either the developing cortex or the hippocampus. 
 Ventricular co-injection and electroporation of a luciferase gene allowed monitoring of the transfected cells postnatally after intraperitoneal luciferin injection in the anesthetized live P7 pup by in vivo bioluminescence, using an IVIS Spectrum device with 3D quantification software. 
 Area definition by bioluminescence could clearly differentiate between cortical and hippocampal electroporations and detect a signal longitudinally over time up to 5 weeks after birth. This imaging technique allowed us to select pups with a sufficient number of transfected cells assumed necessary for triggering biological effects and, subsequently, to perform behavioral investigations at 3 month of age. As an example, this study demonstrates that IUE with the human full length DISC1 gene into the rat cortex led to amphetamine hypersensitivity. Co-transfected GFP could be detected in neurons by post mortem fluorescence microscopy in cryosections indicating gene expression present at &ge;6 months after birth.
 We conclude that postnatal bioluminescence imaging allows evaluating the success of transient transfections with IUE in rats. Investigations on the influence of topical gene manipulations during neurodevelopment on the adult brain and its connectivity are greatly facilitated. For many scientific questions, this technique can supplement or even replace the use of transgenic rats and provide a novel technology for behavioral neuroscience.

Generation of Topically Transgenic Rats by In utero Electroporation and In vivo Bioluminescence Screening

Genes can be manipulated during development of the cortex or the hippocampus of the rat via in utero electroporation (IUE) at E16, to enable fast and targeted modifications in neuronal connectivity for later studies of behavior or neuropathology in adult animals. Postnatal in vivo imaging for control of IUE success is performed by bioluminescence of activating co-transfected luciferase.

外用转基因大鼠通过代<em&gt;在子宫内</em&gt;电穿孔和<em&gt;在体内</em&gt;生物发光筛选

 In utero electroporation (IUE) is a technique which allows genetic modification of cells in the brain for investigating neuronal development. So far, the ...

Motor Nerve Transection and Time-lapse Imaging of Glial Cell Behaviors in Live Zebrafish

The nervous system is often described as a hard-wired component of the body even though it is a considerably fluid organ system that reacts to external stimuli in a consistent, stereotyped manner, while maintaining incredible flexibility and plasticity. Unlike the central nervous system (CNS), the peripheral nervous system (PNS) is capable of significant repair, but we have only just begun to understand the cellular and molecular mechanisms that govern this phenomenon. Using zebrafish as a model system, we have the unprecedented opportunity to couple regenerative studies with in vivo imaging and genetic manipulation. Peripheral nerves are composed of axons surrounded by layers of glia and connective tissue. Axons are ensheathed by myelinating or non-myelinating Schwann cells, which are in turn wrapped into a fascicle by a cellular sheath called the perineurium. Following an injury, adult peripheral nerves have the remarkable capacity to remove damaged axonal debris and re-innervate targets. To investigate the roles of all peripheral glia in PNS regeneration, we describe here an axon transection assay that uses a commercially available nitrogen-pumped dye laser to axotomize motor nerves in live transgenic zebrafish. We further describe the methods to couple these experiments to time-lapse imaging of injured and control nerves. This experimental paradigm can be used to not only assess the role that glia play in nerve regeneration, but can also be the platform for elucidating the molecular mechanisms that govern nervous system repair.

Although the peripheral nervous system (PNS) is capable of significant repair after injury, little is known about the cellular and molecular mechanisms that govern this phenomenon. Using live, transgenic zebrafish and a reproducible nerve transection assay, we can study dynamic glial cell behaviors during nerve degeneration and regeneration.

电机神经切断和时间推移成像胶质细胞行为在现场斑马鱼

The  nervous system is often described as a hard-wired component of the body even  though it is a considerably fluid organ system that reacts to external ...

Spinal Cord Transection in the Larval Zebrafish

Mammals fail in sensory and motor recovery following spinal cord injury due to lack of axonal regrowth below the level of injury as well as an inability to reinitiate spinal neurogenesis. However, some anamniotes including the zebrafish Danio rerio exhibit both sensory and functional recovery even after complete transection of the spinal cord. The adult zebrafish is an established model organism for studying regeneration following spinal cord injury, with sensory and motor recovery by 6&#160;weeks post-injury. To take advantage of in vivo analysis of the regenerative process available in the transparent larval zebrafish as well as genetic tools not accessible in the adult, we use the larval zebrafish to study regeneration after spinal cord transection. Here we demonstrate a method for reproducibly and verifiably transecting the larval spinal cord. After transection, our data shows sensory recovery beginning at 2&#160;days post-injury (dpi), with the C-bend movement detectable by 3 dpi and resumption of free swimming by 5 dpi. Thus we propose the larval zebrafish as a companion tool to the adult zebrafish for the study of recovery after spinal cord injury.

After spinal transection, adult zebrafish have functional recovery by six weeks post-injury. To take advantage of larval transparency and faster recovery, we present a method for transecting the larval spinal cord. After transection, we observe sensory recovery beginning at 2&#160;days post-injury, and C-bend movement by 3 days post-injury.

在斑马鱼幼虫脊髓横断

Mammals fail in sensory and motor recovery following spinal cord injury due to lack of axonal regrowth below the level of injury as well as an inability ...

A Lateralized Odor Learning Model in Neonatal Rats for Dissecting Neural Circuitry Underpinning Memory Formation

Rat pups during a critical postnatal period (&#8804; 10 days) readily form a preference for an odor that is associated with stimuli mimicking maternal care. Such a preference memory can last from hours, to days, even life-long, depending on training parameters. Early odor preference learning provides us with a model in which the critical changes for a natural form of learning occur in the olfactory circuitry. An additional feature that makes it a powerful tool for the analysis of memory processes is that early odor preference learning can be lateralized via single naris occlusion within the critical period. This is due to the lack of mature anterior commissural connections of the olfactory hemispheres at this early age. This work outlines behavioral protocols for lateralized odor learning using nose plugs. Acute, reversible naris occlusion minimizes tissue and neuronal damages associated with long-term occlusion and more aggressive methods such as cauterization. The lateralized odor learning model permits within-animal comparison, therefore greatly reducing variance compared to between-animal designs. This method has been used successfully to probe the circuit changes in the olfactory system produced by training. Future directions include exploring molecular underpinnings of odor memory using this lateralized learning model; and correlating physiological change with memory strength and durations.

This protocol introduces lateralized early odor preference learning in rats using acute single naris occlusion. Lateralized learning permits the examination of behavioral outcomes and underpinning biological mechanisms within the same animals, reducing variance induced by between-animal designs. This protocol can be used to investigate molecular mechanisms underpinning early odor learning.

新生大鼠于A气味偏侧学习模型解剖神经回路托换记忆的形成

Rat pups during a critical postnatal period (&#8804; 10 days) readily form a preference for an odor that is associated with stimuli mimicking maternal ...

Partial Optic Nerve Transection in Rats: A Model Established with a New Operative Approach to Assess Secondary Degeneration of Retinal Ganglion Cells

Previous studies have shown that the secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. Partial optic nerve transection is considered a useful and reproducible model. Compared with other optic nerve injury models used commonly for assessing secondary degeneration, e.g. complete optic nerve transection and optic nerve crush models, the partial optic nerve transection model is superior as it distinguishes primary from secondary degeneration in situ. Therefore, it serves as an excellent tool for evaluating secondary degeneration. This study describes a novel operative approach of partial optic nerve transection by directly accessing the area of the retrobulbar optic nerve through the orbital lateral wall of the eyeball. Moreover, we present a newly designed, low cost surgical instrument to assist with transection. As demonstrated by the representative results in distinguishing the boundary of primary and secondary injury areas, the new approach and instrument ensures high efficiency and stability of the model by providing adequate space for surgical operation. This in turn makes it easy to separate the meningeal sheath and ophthalmic vessels from the optic nerve before transection. An additional benefit is that this space-saving operative approach improves the investigators&#39; ability to administer drugs, carriers, or selective RGC tracers to the stump of the partially transected optic nerve, allowing the exploration of mechanisms behind secondary injury in RGCs, in a new way.

Secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. This study describes an innovative operative approach for partial optic nerve transection. The use of this space-saving operative approach extends the model's application range, and allows exploration of secondary injury mechanisms in RGCs in a new way.

大鼠部分视神经切断术: 建立一种新的手术方法评价视网膜神经节细胞二次变性的模型

Previous studies have shown that the secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. Partial optic nerve transection ...

Sub-acute Cerebral Microhemorrhages Induced by Lipopolysaccharide Injection in Rats

Cerebral microhemorrhages (CMHs) are common in aged patients and are correlated to various neuropsychiatric disorders. The etiology of CMHs is complex, and neuroinflammation is often observed as a co-occurrence. Here, we describe a sub-acute CMHs rat model induced by lipopolysaccharide (LPS) injection, as well as a method for detecting CMHs. Systemic LPS injection is relatively simple, economical, and cost-effective. One major advantage of LPS injection is its stability to induce inflammation. CMHs caused by LPS injection could be detected by gross observation, hematoxylin and eosin (HE) staining, Perl&#39;s Prussian staining, Evans blue (EB) double-labeling, and magnetic resonance imaging-susceptibility weighted imaging (MRI-SWI) technology. Finally, other methods of developing CMHs animal models, including their advantages and/or disadvantages, are also discussed in this report.

We present a protocol to induce and detect CMHs caused by LPS injection in Sprague-Dawley rats, which may be utilized in future research investigations on the pathogenesis of CMHs.

脂多糖注射液致大鼠亚急性脑 Microhemorrhages

Cerebral microhemorrhages (CMHs) are common in aged patients and are correlated to various neuropsychiatric disorders. The etiology of CMHs is complex, ...