Pioro E P, Ribeiro-Da-Silva A, Cuello A C
Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada.
J Comp Neurol. 1991 Mar 8;305(2):189-200. doi: 10.1002/cne.903050203.
The intracellular distribution of nerve growth factor receptor immunoreactivity was examined by electron microscopy in the cerebellum of adult and postnatal day 12 rats. The very faint immunostaining in Purkinje cells of naive adult animals was greatly amplified after colchicine treatment. Neonatal cerebellum, in contrast, contained prominent immunoreactivity in both Purkinje cells and germinal cells of the external granular layer. Intracellular distribution of the nerve growth factor receptor reaction product was very similar in Purkinje cells of both neonatal and colchicine-treated adult animals. It was consistently present along the perikaryal cell membrane, in segments of the rough endoplasmic reticulum and Golgi complex. Numerous membrane-bound aggregates of immunoreactive vesicles resembling multivesicular bodies (secondary lysosomes) were scattered throughout the cell soma, although less frequently in neonatal rats. Bulbous expansions along the proximal axons of colchicine-treated Purkinje cells were filled with such immunoreactive multivesicular bodies. These cells also displayed evidence of nerve growth factor receptor internalization in the form of immunoreactive coated vesicles situated near the cell membrane. In addition to the staining in Purkinje cells, neonatal cerebellum contained high amounts of nerve growth factor receptor reaction product along the cell membrane of germinal cells in the external granular layer. Although Purkinje cells of naive adult animals possessed little or no cell membrane-related nerve growth factor receptor immunoreactivity, reaction product was sometimes seen in cisternae of the rough endoplasmic reticulum and Golgi apparatus. These findings provide electron microscopic immunocytochemical evidence of nerve growth factor receptor synthesis, internalization, and catabolism in noncholinergic neurons of the central nervous system.
通过电子显微镜检查成年大鼠和出生后第12天大鼠小脑内神经生长因子受体免疫反应性的细胞内分布。未处理的成年动物浦肯野细胞中非常微弱的免疫染色在秋水仙碱处理后大大增强。相比之下，新生小脑的浦肯野细胞和外颗粒层的生发细胞中均含有明显的免疫反应性。新生动物和经秋水仙碱处理的成年动物的浦肯野细胞中神经生长因子受体反应产物的细胞内分布非常相似。它始终存在于核周细胞膜、粗面内质网片段和高尔基体中。许多类似于多泡体（次级溶酶体）的免疫反应性囊泡的膜结合聚集体散布在整个细胞体中，不过在新生大鼠中出现的频率较低。秋水仙碱处理的浦肯野细胞近端轴突上的球状膨大充满了这种免疫反应性多泡体。这些细胞还显示出以位于细胞膜附近的免疫反应性被膜小泡形式存在的神经生长因子受体内化的证据。除了浦肯野细胞中的染色外，新生小脑的外颗粒层生发细胞膜上还含有大量神经生长因子受体反应产物。尽管未处理的成年动物的浦肯野细胞几乎没有或没有与细胞膜相关的神经生长因子受体免疫反应性，但有时在粗面内质网和高尔基体的潴泡中可见反应产物。这些发现提供了中枢神经系统非胆碱能神经元中神经生长因子受体合成、内化和分解代谢的电子显微镜免疫细胞化学证据。
