大鼠尾动脉平滑肌中多巴胺受体亚型分布的分析  

Both dopamine 1 and dopamine 2 receptors exist in the rat caudal artery

作　　者：张红[1] 张梅[1] 赵荣瑞[1] 

机构地区：[1]山西医科大学生理学教研室

出　　处：《山西医科大学学报》1998年第2期97-99,共3页Journal of Shanxi Medical University

基　　金：国家自然科学基金

摘　　要：长期以来认为在内脏血管中含有两种亚型的多巴胺受体ＤＡ１和ＤＡ２，而躯体血管中只存在多巴胺受体ＤＡ２亚型。但在实验中偶然发现大鼠尾动脉对ＤＡ１亚型特异性激动剂ｆｅｎｏｌｄｏｐａｍ有明显反应，因此应用离体血管环法和反转录聚合酶链反应方法对大鼠尾动脉平滑肌中多巴胺受体两亚型的分布情况进行了观察。结果显示：亚型选择性多巴胺受体激动剂ｆｅｎｏｌｄｏｐａｍ和ＰＢＤＡ（ＤＡ２亚型激动剂）在尾动脉均产生浓度依赖性舒张反应，该效应分别被亚型特异性拮抗剂部分或完全阻断；来自尾动脉之ＲＮＡ的ＰＣＲ结果可见到预期长度为２４７ｂｐ的特异性阳性扩增条带，而未加反转录酶之结果呈现阴性，说明该产物来自ｃＤＮＡ而非基因组ＤＮＡ。In the peripheral vasculature,the somatic artery has long been regarded as having only dopamine 2 receptor subtype without having dopamine 1 receptor subtype in it However,in experimental studies it was found that the rat caudal arterial rings were also responsive to dopamine 1 receptor agonist fenoldopam So the reverse transcription polymerase chain reaction technique and isolated blood vessel ring bioassay were employed to reexamine the dopamine receptor subtypes in the rat caudal artery It was shown that both selective dopamine 1 and dopamine 2 receptor agonists could induce a dose dependent vasorelaxation in rat caudal arteries that could be completely and partly antagonized by the highly selective dopamine 1 antagonist,SCH23390 A predicted size product(247bp)was evident from caudal artery RNA PCR performed in the absence of reverse transcriptase did not result in an amplification of the predicted product,indicating that these products were from cDNA and not from genomic DNA The findings suggest that both dopamine 1 and dopamine 2 subtypes are existed in the rat caudal arteries

关 键 词：尾动脉 平滑肌 多巴胺受体 亚型分布 

分 类 号：R337[医药卫生—人体生理学]