Kim Younghwa, Oh Seikwan
Department of Anatomy, College of Medicine, Ewha Womans University, Seoul 158-710, Korea.
Neurochem Res. 2002 Jun;27(6):527-33. doi: 10.1023/a:1019808905500.
Pentobarbital was continuously infused intracerebroventricularly (i.c.v.) at the rate of 300 micrograms/10 microliters/h for 7 days, and withdrawal from pentobarbital was rendered 24 h after the stopping of the infusion. To eliminate the induction of hepatic metabolism by systemic administration of pentobarbital, an i.c.v. infusion model of tolerance to and withdrawal from pentobarbital was used. Little is known about the functional modulation of the G protein alpha-subunits at the molecular level. The effects of continuous infusion of pentobarbital on the modulation of G protein alpha-subunits mRNA were investigated by using in situ hybridization study. In situ hybridization showed that the level of G alpha s mRNA was increased in the septum and brainstem, and the level of G alpha o mRNA was elevated in the cortex during the pentobarbital withdrawal. The level of G alpha i mRNA was significantly elevated in almost all area of brain during the pentobarbital withdrawal. These results suggest that region-specific changes of G protein alpha-subunit mRNA were involved in the withdrawal from pentobarbital, whereas alpha-subunit is not so highly involved in the pentobarbital tolerance.
戊巴比妥以300微克/10微升/小时的速率持续脑室内注射（i.c.v.）7天，并在输注停止后24小时进行戊巴比妥戒断。为消除戊巴比妥全身给药对肝脏代谢的诱导作用，采用了戊巴比妥耐受和戒断的脑室内输注模型。关于G蛋白α亚基在分子水平上的功能调节知之甚少。通过原位杂交研究探讨了戊巴比妥持续输注对G蛋白α亚基mRNA调节的影响。原位杂交显示，在戊巴比妥戒断期间，隔区和脑干中Gαs mRNA水平升高，皮质中Gαo mRNA水平升高。在戊巴比妥戒断期间，几乎所有脑区的Gαi mRNA水平均显著升高。这些结果表明，G蛋白α亚基mRNA的区域特异性变化参与了戊巴比妥的戒断，而α亚基在戊巴比妥耐受中参与程度不高。
