An ultrastructural study of glomeruli associated with vomeronasal organs transplanted into the rat CNS.
An ultrastructural study of glomeruli associated with vomeronasal organs transplanted into the rat CNS.
复制标题
与移植到大鼠中枢神经系统的犁鼻器官相关的肾小球的超微结构研究。
DOI：
10.1007/bf00186690
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Graziadei,PP
中科院分区：
文献类型：
--
作者：
Morrison,EE;Graziadei,PP
将新生大鼠犁鼻器官移植到仔鼠顶叶皮质，观察其存活情况和轴突向周围宿主脑实质生长的行为。存活10~100天后，取脑组织进行超微结构检查。移植的犁鼻器(VNO)形成多个囊泡，内衬感觉上皮。从这些感觉上皮细胞，VNO神经元离开上皮细胞进入宿主大脑。移植神经元生长出轴突，这些轴突被鞘细胞突起包围成束，并形成一个或多个含有明显球状或球形肾小球结构的纤维丛。肾小球由神经末梢组成，神经末梢之间存在不对称突触联系。我们很少观察到明显的相互突触。肾小球还含有终末变性的迹象，如终末密度增加，线粒体成团，多泡小体。肾小球没有被胶质隔膜分割或细分，但神经胶质轮廓散布在感觉终末之间。移植肾小球也缺乏小球周细胞，也没有明确的神经胶质包膜。这些结果表明，肾小球的形成不依赖于二级神经元的树突贡献或神经胶质支持，而是依赖于互补的受体神经元群体。
Rat neonate vomeronasal organs were transplanted into the parietal cortex of littermates to examine their survival and the behavior of axon growth into the surrounding host brain parenchyma. After survival times of 10–100 days the brains were processed for ultrastructural examination. The transplanted vomeronasal organs (VNO) formed several vesicles lined with a sensory epithelium. From these sensory epithelia, VNO neurons leave the epithelium and enter the host brain. Transplant neurons grew axons that fasciculated into bundles surrounded by sheath cell processes and formed one or more fiber plexuses containing distinct globose or spherical-shaped glomeralar-like structures. The glomeruli consisted of nerve terminals between which existed asymmetric synaptic contacts. Rarely did we observe clear reciprocal synapses. The glomeruli also contained terminals that showed signs of degeneration, such as increased density of the terminals, clumping of mitochondria and multivesicular bodies. The glomeruli were not partitioned or subdivided by glial septa; however, glial profiles were interspersed among the sensory terminals. Transplant glomeruli also lacked periglomerular cells and had no definitive glial envelope. These results suggest that glomerular formation is not dependent on dendrite contribution of second order neurons or glial support, but rather on a complementary population of receptor neurons.