ALTERATIONS IN AFFERENT PATHWAYS FROM THE URINARY-BLADDER OF THE RAT IN RESPONSE TO PARTIAL URETHRAL OBSTRUCTION
ALTERATIONS IN AFFERENT PATHWAYS FROM THE URINARY-BLADDER OF THE RAT IN RESPONSE TO PARTIAL URETHRAL OBSTRUCTION
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DOI：
10.1002/cne.903100309
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发表时间：
1991-08-15
影响因子：
2.5
通讯作者：
DEGROAT, WC
中科院分区：
文献类型：
--
作者：
STEERS, WD;CIAMBOTTI, J;DEGROAT, WC
在正常雌性Wistar大鼠以及部分尿道结扎的大鼠中，利用轴突追踪技术对来自膀胱的传入通路进行了研究。将麦胚凝集素 - 辣根过氧化物酶（HRP）注入膀胱壁后，在腰骶背根神经节细胞以及已知接受内脏传入输入的L6 - S1脊髓的Ⅰ、Ⅱ、Ⅴ - Ⅶ和Ⅹ板层部位的传入投射中检测到了HRP。部分尿道结扎（6周）使膀胱重量增加了6倍，并改变了膀胱传入通路的形态。变化包括与对照组大鼠（528±189μm²）相比，梗阻组大鼠L6和S1背根神经节中标记的神经元轮廓的平均横截面积增加（766±378μm²，P < 0.001）。最大轮廓的横截面积也增加了约40%。标记的背根神经节细胞轮廓的平均数量在结扎组（837±198）和对照组（883±352）中相似。与对照组动物相比，梗阻动物在L6 - S1脊髓中间外侧区域标记的传入终末区域面积增加了60%。考虑到注入肥大膀胱的每单位膀胱重量的示踪剂体积比对照组少87%，这种标记增加更为显著。这些结果提供的证据表明，膀胱传入神经投射到已知调节排尿的脊髓区域，并且这些传入神经可因尿道结扎而发生形态改变和/或轴浆运输变化。这些变化可能是由于靶器官质量增加、神经活动增强或神经营养因子水平或活性改变而发生的。
Afferent pathways from the urinary bladder were examined with axonal tracing techniques in normal female Wistar rats and in those with partial urethral ligation. Following injection of wheat germ agglutinin-horseradish peroxidase (HRP) into the bladder wall, HRP was detected in lumbosacral dorsal root ganglion cells and in afferent projections to the L6-S1 spinal cord at sites in laminae I, II, V-VII, and X known to receive visceral afferent input. Partial urethral ligation (6 weeks) produced a sixfold increase in bladder weight and altered the morphology of bladder afferent pathways. Changes included an increase in the average cross-sectional area of labelled neuronal profiles in L6 and S1 dorsal root ganglia in obstructed (766 +/- 378-mu-m2, P < 0.001) compared to control rats (528 +/- 189-mu-2). The cross-sectional area of the largest profiles also increased by approximately 40%. The mean number of labelled dorsal root ganglion cell profiles was similar in ligated (837 +/- 198) and control (883 +/- 352) groups. When compared to control animals the obstructed animals exhibited a 60% increase in the area of the labelled afferent terminal field in the intermediolateral region of the L6-S1 spinal cord. This increased labelling was even more remarkable given that the volume of tracer per bladder weight injected into the hypertrophied bladder was 87% less than controls. These results provide evidence that bladder afferents project to regions of the spinal cord known to regulate micturition and that these afferents can undergo morphological alterations and/or changes in axoplasmic transport in response to urethral ligation. Changes may occur in response to increased target organ mass, increased neural activity, or alterations in the levels or activity of neurotrophic factors.