Caspase-3在成年大鼠中枢神经系统分布的免疫组织化学研究

采用免疫组织化学ABC法观察caspase3在成年大鼠中枢神经系统不同区域内的分布。caspase3阳性反应产物主要分布于脊髓前角和侧角大型运动神经元及中型神经元的胞浆、胞核及突起;脊髓后角及灰质连合的中、小型神经元的胞核及胞浆亦可见caspase3阳性反应产物;脊髓白质内的星形胶质细胞、小胶质细胞及少突胶质细胞的胞核和胞浆,caspase3阳性反应产物呈强阳性反应。在延髓内,caspase3阳性反应产物定位于中央灰质、三叉神经尾侧亚核和中央网状核内中型神经元的胞浆。大脑皮层各区内的caspase3阳性反应产物集中分布于ⅢⅤ层锥体细胞的胞浆,呈弱阳性反应。海马的CA1、CA2、CA3、CA4区的锥体细胞层的细胞,胞浆亦呈弱阳性反应。小脑内,以Purkinje细胞胞浆着色为主。乳头体核、尾状核、豆状核、嗅前核后部、嗅结节及丘脑等部位亦可见caspase3阳性神经元。本研究的结果说明caspase3在中枢神经系统内广泛分布,且在不同部位神经元的亚细胞分布存在差异。

IMMUNOHISTOCHEMICAL STUDY ON THE DISTRIBUTION OF CASPASE-3 IN CENTRAL NERVOUS SYSTEM OF THE ADULT RAT

Immunohistochemical avidin-biotin-peroxidase-complex (ABC) method was used to investigate the distribution of caspase-3-like immunopositive products in central nervous system (CNS). In ventral horn and lateral horn of spinal cord, caspase-3-like immunoreactive products were located in cytoplasm and nuclei as well as neural processes of large motor neurons and medium-sized neurons. Moreover, caspase-3-like immunoreactive products were also detected in some medium and small-sized neurons in dorsal horn and gray commissure. In white matter of the spinal cord, caspase-3-like immunoreactivities expressed strongly in astrocyte, microglia and oligodendrocyte. For medulla oblongata, caspase-3-like immunoreactivities could be found in cytoplasm of medium-sized neurons in central gray matter, caudal subnucleus of the spinal trigeminal nucleus, central reticular nucleus of medulla oblongata. In cerebral cortex, caspase-3-like immunopositivities neurons mainly distributed in cytoplasm of the pyramid cells in Ⅲ-Ⅴ layers and their staining was weak. As for CA1, CA2, CA3, CA4 of hippocampus, caspase-3-like immunoreactivities were detected only in cytoplasm of pyramid cell layer and their staining was also weak. In cerebellar cortex, caspase-3-like immunoreactivities were observed in cytoplasm of Purkinje cells. Besides that, caspase-3-like immunopositive products could be found in caudate nucleus, lentiform nucleus, nuclei in mammillary region, posterior part of anterior olfactory nucleus, olfactory tubercle and thalamus. The present results indicate that caspase-3 extensively present in different neurons and glial cells in the CNS and the distribution of sub-cellular of caspase-3 vary with different parts in the CNS.