异戊酸对非洲爪蟾卵母细胞膜上α1甘氨酸受体氯离子通道电流的影响

Effect of isovaleric acid on the chloride channel current of alpha-1 glycine receptor on membrane of Xenopus laevis oocyte

目的探讨异戊酸对甘氨酸受体氯离子通道的影响。方法采用微注射法在非洲爪蟾卵母细胞核中注射α1甘氨酸受体cDNA,在细胞膜上过度表达甘氨酸受体后,采用双电极全细胞膜片钳技术测定异戊酸对该受体氯离子通道电流变化的影响。结果5．0～20 mmol/L异戊酸可增强卵母细胞膜上甘氨酸受体氯离子通道内流电流（19%～187%,P＜0．01）,且呈浓度依赖性。结论异戊酸对α1甘氨酸受体氯离子通道电流有增强作用,其镇静催眠作用的机制可能与此有关。

Objective To investigate the effect of isovaleric acid on the current of alpha-1 glycine receptor chloride channel on the membrane of Xenopus laevis oocyte. Methods cDNA of glycine receptor was microinjected into the nuclear of Xenopus laevis oocytes for the over-expression of glycine receptors. One or two days after injection, two-electrede voltage clamping was performed to measure the chloride channel current on the oocyte membrane after the topical administration of 5.0, 7.5, 10 or 20 mmol/L isovaleric acid. Results The application of isovaleric acid increased the glycine-induced chloride ion current in a concentration-dependent manner. Conclusion Isovaleric acid at the concentration of 5.0-20 mmol/L modulates the glycine receptors by increasing the chloride channel current. This enhancement on the inhibitory neurotransmitter receptor might contribute to the sedative and hypnotic effect of isovaleric acid.