严重创伤早期大鼠下丘脑G蛋白偶联受体激酶的变化  

Change of hypothalamic G protein-coupled receptor kinase in rats early after severe trauma

作　　者：谭浩[1] 许民辉[1] 周继红[2] 邹咏文[1] 张云东[1] 

机构地区：[1]第三军医大学大坪医院野战外科研究所神经外科,重庆400042 [2]第三军医大学大坪医院野战外科研究所交通医学研究所,重庆400042

出　　处：《中华神经医学杂志》2005年第2期130-132,共3页Chinese Journal of Neuromedicine

基　　金：国家"973"创伤项目01课题(G1999054201)

摘　　要：目的研究G蛋白偶联受体激酶(GRK)在大鼠下丘脑的分布和严重创伤后时相变化及其与应激早期下丘脑促肾上腺皮质激素释放激素(CRH)分泌的关系。方法采用胸部撞击和单侧股骨中段骨折进行致伤。50只成年Wistar大鼠随机分为正常对照组和创伤组,通过免疫组化实验研究GRK在下丘脑的分布,Westernblot实验研究室旁核GRK的蛋白表达,RT-PCR技术研究室旁核CRH的转录活性。结果在下丘脑室旁核有GRK2/3的分布,但未发现GRK6的阳性染色;GRK2/3的总蛋白在创伤后30min显著下降(P<0.05),90min恢复近正常水平;CRHmRNA表达在伤后30min显著升高(P<0.05),60min、90min的升高非常显著(P<0.01)。结论在创伤应激过程早期GRK2/3的蛋白表达受到了抑制,推测下丘脑室旁核促肾上腺皮质激素释放激素1型受体(CRHR1)的同源性脱敏受到了抑制,间接促进了下丘脑室旁核CRH的分泌。Objective To study the distribution of G protein-coupled receptor kinase (GRK) in rats' hypothalami and its role in the secretion of corticotrophin-releasing hormone (CRH) early after severe trauma. Methods The trauma was made by severe thorax impact and unilateral femur fracture. 50 Wistar adult rats were randomized as control group and traumatic group. The distribution of hypothalamic GRK and the expression of GRK of paraventricular nucleus (PVN) were measured by immunohistochemistry and Westernblot respectively. CRH mRNA was detected by RT-PCR. Results The positive stain of GRK2/3, not GRK6, was found mostly in the PVN of hypothalamus. GRK2/3 decreased significantly 30 min after trauma (P<0.05) and nearly recovered 90 min after trauma. A remarkable increase of CRH mRNA was observed 30 min after trauma (P<0.05), and more significant 60 min, 90 min after trauma (P<0.01). Conclusion GRK2/3 is inhibited early after trauma, which suggests the homologous desensitization of corticotrophin-releasing hormone receptor 1 (CRHR1) in hypothalamus may be inhibited and increase the secretion of CRH indirectly.

关 键 词：CRH 下丘脑室旁核 严重创伤 早期 成年WISTAR大鼠 G蛋白偶联受体激酶 正常 创伤应激 分泌 转录活性 

分 类 号：R642.02[医药卫生—外科学]