论文部分内容阅读
为深入探索脊髓的可塑性变化规律，用５只单侧腰骶背根全切猫，术后存活３～４个月。发现实验侧脊髓Ⅱ板层内背根来源的复合终末数下降至正常的２４％；非背根来源的简单终末数却增加至正常的１３４％；还新发现了一类双重突触性终末，本文将之称为非典型复合终末。上述变化使突触总数仍维持在正常水平。在Ｌ＿６节段的简单终末中，形成对称性突触的简单终末，其增幅（７１％）显著地大于形成非对称性突触者（３６％）；含有致密核心小泡的简单终末，其增幅（１１９％）又明显地大于仅含清亮小泡者（３４％）。这种简单终末各亚类的增幅不同，可能与丢失大量背根来源的复合终末后进行的机能调整有关。还发现一个树突截面上同时与两个简单终末形成突触的机率增加了４４％。其中含一个对称性突触者更成倍增加，达正常的２１９％。表明新形成的简单终末，除与丢失终末存留的突触后部位恢复突触性联系外，还可能有新的突触性联系形成。
In order to explore the changing rules of the plasticity of the spinal cord in depth, 5 cats with lumbosacral dorsal root were cut completely to survive for 3 to 4 months. Found that the number of dorsal root-derived composite terminals in the experimental spinal cord II platelet decreased to 24% of normal; simple terminal numbers derived from non-dorsal roots increased to 134% of normal; a new class of double-synaptic Terminal, this article will be called atypical composite terminal. The above changes make the total number of synapses remained at normal levels. In the simple terminal of the L_6 segment, a simple terminal for a symmetric synapse was formed with an amplitude (71%) significantly greater than those forming asymptomatic synapses (36%); a simple terminal with dense core vesicles The increase (119%) was significantly greater than those with clear vesicles (34%). The increase in each subclass of this simple terminal may be related to a functional adjustment after the loss of a large number of composite terminals derived from the dorsal root. It was also found that the probability of forming synapses simultaneously with two simple terminals on a dendritic section increased by 44%. Including a symmetrical synapse more doubled, up to 219% of normal. Indicating that the newly formed simple terminal, in addition to the loss of the terminal survival of the postsynaptic recovery of synaptic contact, but also may have new synaptic connections.