Neuropharmacological studies on the roles of glial receptors for neurotransmitters in gliosis

神经胶质细胞在脑损伤中起一定作用，但具体机制尚不清楚。本课题通过对受体（谷氨酸、内皮素和前列腺素）、谷氨酸转运体和Na^+、K^+- atp酶的研究，阐明脑内胶质细胞的生理和病理作用。得到了以下结果：在培养的大鼠星形胶质细胞中，谷氨酸引起肿胀和牛磺酸释放。肿胀是由嗜离子性谷氨酸受体和谷氨酸转运体介导的。星形胶质细胞中谷氨酸转运蛋白抑制剂与代谢性谷氨酸受体相互作用。内皮素引起培养的星形胶质细胞形态学改变。我们的研究表明，肽通过小G蛋白调节细胞骨架蛋白的组织。体内内皮素可增加大鼠脑内gfap阳性细胞的数量。明确了星形胶质细胞中前列腺素F2a和血栓素A2受体的结构和表达。igf - 1在培养的星形胶质细胞中引起Na^+， K^+- atp酶的异构体特异性诱导。这种诱导可能与肽对星形胶质细胞的有丝分裂作用有关。

It is considered that glial cells have a role in brain injury, but exact mechanism is not known. In this project, the studies on receptors (glutamate, endothelins and prostaglandins) , glutamate transporter and Na^+, K^+-ATPase were carried out, in order to clarify the physiological and pathological roles of glial cells in brain. The following results were obtained.1. In cultured rat astrocytes, glutamate caused swelling and taurine release. The swelling was mediated via ionotropic glutamate receptors and glutamate transporters.2. Inhibitors of glutamate transporter interacts with metabotropic glutamate receptors in astrocytes.3. Endothelins caused a morphological change in cultured astrocytes. Our studies demonstrate that the peptides modulate cytoskeletal protein organization via a small G protein.4. Endothelin in vivo increased the number of GFAP-positive cells in rat brain.5. Structure and expression of prostaglandin F2a and thromboxane A2 receptors were clarified in astrocytes.6. IGF-I caused a isoform-specific induction of Na^+, K^+-ATPase in cultured astrocytes. The induction may be involved in the mitogenic action of the peptide on astrocytes.