药物对小白鼠不同脑区GABA_A受体与外源性GABA_A结合的影响

用同位素示踪法测定药物对小鼠四个不同脑区的GABA_A受体与外源性GABA结合的影响。GABA_A受体颉颃剂Picrotoxin,bicuculline,青霉素,和GABA-T抑制剂AOAA均使大脑皮层的受体结合显著增加,中枢兴奋剂戊四唑使之显著地减少。AOAA使海马的受体结合显著增加,戊四唑及安定使之显著减少。蝎毒使下丘脑的受体结合显著增加,而戊四唑使之显著减少。AOAA、蝎毒、bicuculline、picrotoxin使小脑的受体结合显著增加。

EFFECTS OF SOME DRUGS ON [~3H]-GABA BINDING WITH GABAA RECEPTOR IN DIFFERENT AREAS OF BRAIN IN MOUSE

The effects of drugs on the binding of ~3H]-GABA with GABA_A receptor in four areas of the brain in a mouse were shown by way of incubating homogenate together with ~3H]-GABA in vitro. The results are as follows: (1) GABA_A antagonists, picrotoxin, bicuculline and penicillin markedly increased the binding of ~3H]-GABA to GABAA receptor in the cerebral cortex. Aminooxyacetic acid (AOAA) as an inhibitor of GABA aminotransferase (GABA-T) had the same effect. On the contrary, pentylenetetrazol could markedly decreasethe binding. (2) AOAA significantly increased the binding of ~3H]-GABA to the GABA_A receptor in the hippocam pus, but pentylenetetrazol and diazepam decreased the binding. (3) Martensit-toxin markedly increased the binding in the hypothalamus, and pentylenetetrazol had the same effect as it did in the cerebral cortex and hippocamus. (4) Picrotoxin, bicuculline, AOAA and martensit-toxin significantly increased the binding in the cerebellum. (5) Glutamic acid had no effect on the binding of ~3H]-GABA to GABA_A receptor in the four areas of the mouse brain.