海洛因对大鼠谷氨酸脱氢酶基因表达的影响

目的:研究海洛因对大鼠谷氨酸脱氢酶(GDH)基因表达的影响。方法:40只成年♂Wistar大鼠随机分为4组:对照组腹腔注射(ip)生理盐水9d;给药3d组ip海洛因3d;给药9d组ip海洛因9d;停药组ip海洛因9d后停药8d。采用生化自动分析系统检测血浆及组织中GDH活性,逆转录聚合酶链反应法(RT-PCR)检测组织中GDHmRNA的含量。结果:血浆中GDH活性在海洛因给药期间逐渐增高,停药8d后仍无明显降低;大脑组织GDH活性在海洛因给药3d、海洛因给药9d及停药8d后均显著低于对照组(P<0·01);肝脏GDH活性在海洛因给药过程中降低(P<0·01),停药8d后恢复到对照组水平;小肠GDH活性在海洛因给药9d后显著高于对照组(P<0·05),停药8d后小肠GDH活性继续升高并明显高于对照组(P<0·01)和海洛因给药9d组(P<0·05)。大脑、肝脏和小肠GDHmRNA含量分别与其GDH活性变化趋势一致。结论:海洛因对大鼠不同组织GDH基因表达影响不同。

EFFECTS OF HEROIN ON GLUTAMATE DEHYDROGENASE GENE EXPRESSION IN RATS

Objective: To determine heroin effects on gene expression of glutamate dehydrogenase(GDH) in plasma and tissues of rats . Methods: Forty adult male Wistar rats were evenly divided into 4 groups: control group was peritoneal injected(ip) normal saline for 9 days; two study groups were ip heroin for 3 days and 9 days respectively; withdrawal group was ip heroin for 9 days followed by withdrawal for 8 days. GDH activities in plasma and tissues of the four groups were detected by applying automatic biochemistry analysis system and GDH mRNA in tissues was detected by RT-PCR. Results: Plasma GDH activities increased gradually during heroin administration and remained higher than control group even after withdrawal for 8 days (P<0.01). GDH activities in cerebrum of 3 day and 9 day heroin administration group and withdrawal group dramatically decreased compared with control group(P<0.01). Liver GDH activity reduced during heroin treatment(P<0.01) and returned to the same leve1 as control after withdrawal for 8 days. Small intestine GDH activity increased after 9 day heroin injection(P<0.05) and kept rising after withdrawal for 8 days. GDH mRNA contents in cerebrum, liver and small intestine changed in the same way with GDH activities in corresponding tissues. Conclusion: Heroin has different effects on GDH gene expression in different tissues.