Ranson R N, Dowling P, Santer R M, Watson A H D
Cardiff School of Biosciences, Biomedical Sciences Buildings, Cardiff University, Museum Avenue, Cardiff, UK.
Neuroscience. 2007 Jan 19;144(2):636-44. doi: 10.1016/j.neuroscience.2006.09.036. Epub 2006 Oct 30.
Age-related changes in the number and size of large cholinergic terminals immunoreactive for vesicular acetylcholine transporter (VAChT), were documented for the dorsolateral nucleus (DLN), retrodorsolateral nucleus (RDLN) and spinal nucleus of the bulbospongiosus (SNB) of the lumbosacral spinal cord of male rats. The most significant changes were a large increase in the number and size of cholinergic terminals within the DLN of aged animals, together with a small decrease in terminal number within the RDLN. No significant age-associated differences in VAChT labeling were seen within the SNB. In both age groups, SNB motoneurons projecting to the levator ani muscle received about 9 to 10 contacts from large cholinergic terminals. Ultrastructural examination of the terminals revealed structures likely to be postsynaptic subsurface cisterns that are characteristic of type C terminal boutons. Since both the DLN and SNB contain motoneurons innervating pelvic muscles and sphincters, these findings provide further evidence for a central cholinergic influence on micturition and sexual reflexes and suggest that this may remain robust in the face of ageing.
对雄性大鼠腰骶脊髓的背外侧核（DLN）、后外侧背核（RDLN）和球海绵体肌脊髓核（SNB）中，对囊泡乙酰胆碱转运体（VAChT）免疫反应阳性的大胆碱能终末的数量和大小的年龄相关变化进行了记录。最显著的变化是老年动物DLN内胆碱能终末的数量和大小大幅增加，同时RDLN内终末数量略有减少。在SNB内未观察到与年龄相关的VAChT标记的显著差异。在两个年龄组中，投射到提肛肌的SNB运动神经元从大胆碱能终末接收约9至10个突触联系。对这些终末的超微结构检查显示出可能是C型终末小体特征性的突触后亚表面池的结构。由于DLN和SNB都含有支配盆腔肌肉和括约肌的运动神经元，这些发现为中枢胆碱能对排尿和性反射的影响提供了进一步的证据，并表明面对衰老这种影响可能仍然很强劲。
