中脑导水管周围灰质支配桥脑Barrington's核内骶髓投射神经元的电镜双标记研究

本文研究采用电镜双标记技术对大鼠中脑导水管周围灰质神经元投射到桥脑Barrington's核的轴突与该核内投射到骶髓的神经元的胞体和树突之间的突触关系进行了探讨.将生物素标记的葡聚糖胺(BDA)注射于中脑导水管周围灰质用来标记它发出的轴突终末,将辣根过氧化物酶(HRP)注射于脊髓的骶髓部分,用来标记Barrington's核内投射至骶髓的神经元.显色后透射电镜观察发现,BDA标记的轴突终末与HRP标记的胞体和树突间存在直接的突触联系.此结果提示中脑导水管周围灰质在脑桥排尿反射中可能起着重要的作用.

Direct projections from the periaqueductal gray to spinal cord-projecting neurons in Barrington's: an electron microscopic study in the rat

Direct projections from the periaqueductal gray (PAG) to spinal cord-projecting neurons ofBarrington's nucleus were electron microscopically revealed in the rat by a doublelabeling method.Biotinylated dextran amine (BDA) was injected into the PAG to labelprojection axon terminals originating from the RAG. Horseradish peroxidase (HRP) wasinjected into the lumbosacral cord segments to label neurons projecting to the lumboscralspinal cord. Electron microscopic observation showed that some BDA-labeled axon terminalsmade synaptic contacts with dendrites and somata of HRP-labeled neurons in Barrington'snucleus. The results suggest PAG may be involved in the neuronal mechanisms of the ratmicturition.