Diazoxide increases glutamate uptake by astrocytes via activating mitochondrial ATP-sensitive potassium channels

Abstract

Abstract: AIM: To demonstrate the effect of mitochondrial ATP-sensitive potassium channel opener, Diazoxide, on glutamate uptake activity of astrocyte. METHODS: Primary astrocytic cultures were prepared from cerebral cortices of rats within 3 days old.Glutamate uptake activity of astrocytes was measured using isotopic techniques to detect intracellular [³H]-labeled D, L-glutamate concentration.RESULTS: Diazoxide increased [³H]-glutamate uptake in a concentration-dependent manner, and could significantly reverse MPP⁺-induced glutamate uptake inhibition.The above effects of Diazoxide were blocked by 5-hydroxydecanoate, a selective mitochondrial ATP-sensitive potassium channel blocker. CONCLUSION: Diazoxide increase the activity of glutamate transporters in astrocytes by opening mitochondrial ATP-sensitive potassium channel.

Key words: mitochondrial ATP-sensitive potassium channel, diazoxide, astrocyte, glutamate transporters

CLC Number:

R338.2

DAI Cui-ping, ZENG Xiao-ning, SUN Xiu-lan, DING Jian-hua, HU Gang. Diazoxide increases glutamate uptake by astrocytes via activating mitochondrial ATP-sensitive potassium channels[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2006, 11(4): 398-401.

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