多巴胺D_3受体对大鼠肾脏近曲小管上皮细胞多巴胺D_4受体表达和功能的影响  

Effect of D_3 Dopamine Receptor on D_4 Dopamine Receptor Protein Expression and its Biological Function in Rats' Renal Proximal Tubular Cells

作　　者：陈新建[1] 杨剑[1] 任红梅[1] 陈彩宇[1] 何多芬[1] 王旭开[1] 王红勇[1] 杨成明[1] 周林[1] 曾春雨[1] 

机构地区：[1]中国人民解放军第三军医大学第三附属医院心内科,重庆市400042

出　　处：《中国循环杂志》2011年第2期149-152,共4页Chinese Circulation Journal

基　　金：国家杰出青年科学基金(No.30925018);重庆市杰出青年科学基金(CSTC;2009BA5044);国家自然基金资助项目(No.81070559)

摘　　要：目的:观察多巴胺D3受体(D3受体)对大鼠肾脏近曲小管(RPT)上皮细胞多巴胺D4受体(D4受体)表达和功能的影响。方法:以Wistar-Kyoto(WKY)大鼠RPT上皮细胞为研究对象,利用免疫印迹法观察D3受体激动剂PDl28907刺激D3受体后D4受体表达的变化;采用哇巴因法测定Na+-K+-ATP酶(ATP为三磷酸腺苷)活性,观察D3受体激动剂PDl28907(10-7mol/L,24 h)预先作用后,D4受体激动剂PD168077(10-7mol/L,15 min)对Na+-K+-ATP酶活性的影响。同时,探讨D3受体激动剂PDl28907影响D4受体表达的作用机制。结果:D3受体激动剂PDl28907刺激可明显增强RPT上皮细胞中的D4受体蛋白表达,该作用呈时间与浓度依赖性关系。D3受体激动剂PDl28907对D4受体蛋白表达的增强作用可被D3受体特异性抑制剂U99194A(10-6mol/L)所阻断。磷脂酶C抑制剂U73122存在的情况下,D3受体激动剂PD128907刺激D3受体后对D4受体的促进表达效应受到显著抑制。与单用D4受体激动剂PD168077相比,在PDl28907(10-7mol/L,24 h)预先刺激的情况下,D4受体激动剂PD168077对Na+-K+-ATP酶活性的抑制作用有所增强。结论:D3受体对大鼠RPT上皮细胞上D4受体表达和功能具有增强作用,此作用可能通过磷脂酶C信号途径发挥影响。Objective ：To investigate the effect of D3 dopamine receptor on D4 dopamine receptor protein expression and function in rats＇ renal proximal tubular （RPT）cells. Methods ：Immortalized RPT cells from Wistar-Kyoto rats were stimulated by D3 dopamine receptor agonist PD128907. The protein expression of D4 dopamine receptor was examined by immunoblotting and its biological function was determined by Na＋ - K＋ -ATPase activity. Results： D3 dopamine receptor agonist PD128907 increased D4 dopamine receptor protein expression in RPT cells with a concentration-and time-dependent manner. Stimulation with D4 dopamine receptor agonist PD168077 （10^-7mol/L） decreased the Na＋ -K＋ -ATPase activity in RPT cells, while in PD128907 pretreated cells, the effect of PD168077 on Na＋ -K＋ -ATPase activity was augmented. Those activities were blocked in the presence of D3 receptor antagonist U99194A（ 10^-6 mol/L） or phospholipase C（PLC）blocker U73122 （10^-7mol/L）. Conclusion：D3 dopamine receptor increases D4 dopamine receptor protein expression and biological function in rats＇ RPT cells, PLC pathway might be involved in this biological activity.

关 键 词：多巴胺D3受体 多巴胺D4受体 肾脏近曲小管上皮细胞 

分 类 号：R54[医药卫生—心血管疾病]