高胆固醇抑制孕酮下调豚鼠胆囊平滑肌G_(αi3)蛋白的表达  

High Cholesterol Disrupts the Inhibition of Progesterone on G_(αi3) Protein in Gallbladder Smooth Muscle in Guinea Pig

作　　者：聂云贵[1] 丁佑铭[1] 李红波[1] 汪斌[1] 

机构地区：[1]武汉大学人民医院肝胆腔镜外科,湖北武汉430060

出　　处：《武汉大学学报（医学版）》2013年第5期650-653,共4页Medical Journal of Wuhan University

摘　　要：目的:探讨孕酮在高胆固醇环境下对胆囊平滑肌Gαi3蛋白表达的影响。方法:28只雄性豚鼠按处理因素随机分为正常饮食+生理盐水注射组(NC组)、正常饮食+孕酮注射组(P4组)、高胆固醇饮食+生理盐水注射组(Ch组)和高胆固醇饮食+孕酮注射组(Ch+P4组),每组7只。测量禁食状态下胆囊胆汁量(FB),全自动生化仪测定胆汁中胆固醇(TC)含量,用Western blotting法检测胆囊平滑肌组织的Gαi3蛋白的表达变化。结果:①Ch组、Ch+P4组TC含量高于NC组、P4组(P<0.05);Ch组和Ch+P4组间、NC组和P4组间无明显差异(P>0.05)。②P4组、Ch组的FB明显多于NC组(P<0.05),Ch+P4组的FB与P4组、Ch组相比无显著差异(P>0.05)。③P4组的Gαi3蛋白表达量明显低于NC组(P<0.001),Ch+P4组的Gαi3蛋白表达量低于Ch组而高于P4组(P<0.05),NC组、Ch组间的Gαi3蛋白表达量无明显差异(P>0.05)。结论:孕酮可以明显降低胆囊平滑肌中的Gαi3蛋白表达量,其下调Gαi3蛋白表达的效应可部分被胆固醇阻断,表明孕酮可通过下调收缩功能性Gαi3蛋白损伤胆囊运动,但在胆汁富含胆固醇环境下其作用可能会被削弱。Objective： To identify that whether high cholesterol disrupts the inhibition of progesterone on Gαi3 protein in gallbladder smooth muscle in guinea pig in vivo. Methods： Twenty-eight male guinea pigs were randomly divided into four groups, including group NC （normal diet and injected with 0.9% saline）, group P4 （normal diet and injected with progesterone）, group Ch （2% choles- terol diet and injected with 0.9% saline）, and group Chq-P4 （2% cholesterol diet and injected with progesterone）. Each group had 7 guinea pigs. The fasting volume of bile in gallbladder （FB） which directly reflected the volume of gallbladder was measured by collecting all the bile with syringe. And total cholesterol （TC） of the bile were tested by biochemical analyzer. The specimen was obtained from the body of gallbladder to analyze the Gαi3 protein in gallbladder smooth muscle with Western blotting. Results： The level of TC in group Ch and Ch＋P4 was higher than that of group NC and Pa （P〈0.05）, and there was no significant difference betweengroup Ch and Ch＋P4, and so was the group NC and P4 （P）0. 05）. The FB in group P4 and group Ch were higher than that of group NC （P〈0.05）, but no difference was observed among group Ch, group P4 and group Ch＋P4 （P〉0.05）. The expression of Gαi3protein in group P4 was significantly lower than that of group NC （P〈0. 001）, and the expression of Gαi3protein in group Ch＋P4 was lower than that of group Ch but was higher than that of P4 （P〈0.05）, and no signif- icant difference of Gαi3protein expression between group NC and Ch was observed （P〉0.05）. Conclusion： The Goαi3 protein responsible for contraction in gallbladder smooth muscle can be sig- nificantly downregulated by progesterone, resulting in the dysfunction of motility of gallbladder. However, this effect can be partly blocked by high cholesterol even in vivo, which means the effect of progesterone in gallbladder hypomotility should be reevaluated under high level o

关 键 词：孕酮 Gαi3蛋白 胆囊平滑肌 胆固醇 

分 类 号：R657.42[医药卫生—外科学]