Zhou L, Qiu Z, Ye C, Di L, Liu X, Tang C, Zhao Y
Department of Pathophysiology, Chongqing Medical University, Chongqing 400016, China.
Chin Med J (Engl). 2000 Mar;113(3):269-71.
To investigate the vasoactive effects of adrenotensin and the interactions between adrenotensin and adrenomedullin (ADM).
Isolated rat aortic tension, rat mean arterial pressure and 3H-TdR incorporation of rat vascular smooth muscle cells were measured. Isolated rat aortas were incubated in K-H solution containing adrenomedullin or adrenotensin. The released adrenotensin or adrenomedullin (in incubation medium) from rat aortas was measured by radioimmunoassay.
1 x 10(-8) and 1 x 10(-7) mol/L adrenotensin augmented rat aortic tension in a dose-dependent manner (P < 0.01). An intravenous bolus injection of adrenotensin (2.5 nmol/kg, i.v.) increased the mean arterial pressure by 28% in anesthetized rats (P < 0.01). 1 x 10(-7) mol/L adrenotensin increased 3H-TdR incorporation in cultured rat vascular smooth muscle cells by 55% (P < 0.01). Adrenomedullin inhibited these activities of adrenotensin to different extents. 1 x 10(-9), 1 x 10(-8) and 1 x 10(-7) mol/L adrenotensin decreased adrenomedullin release rates by 19%, 35% and 46%, respectively (P < 0.05 or P < 0.01) and 1 x 10(-8) mol/L adrenomedullin also inhibited adrenotensin release by 45% from rat aorta (P < 0.01).
Adrenotensin is a novel peptide that elicits the activities of vasoconstriction, pressor effects and induces the proliferation of vascular smooth muscle cells. There is antagonism in vascular activities and reciprocal inhibition in the release between adrenotensin and adrenomedullin. These interactions are manifestations of intramolecular regulation of proadrenomedullin (Pro-ADM).
研究肾上腺紧张素的血管活性作用以及肾上腺紧张素与肾上腺髓质素（ADM）之间的相互作用。
测量离体大鼠主动脉张力、大鼠平均动脉压以及大鼠血管平滑肌细胞的3H - 胸腺嘧啶核苷掺入量。将离体大鼠主动脉置于含肾上腺髓质素或肾上腺紧张素的K - H溶液中孵育。采用放射免疫分析法测定大鼠主动脉释放到孵育培养基中的肾上腺紧张素或肾上腺髓质素。
1×10^(-8)和1×10^(-7)mol/L肾上腺紧张素以剂量依赖性方式增强大鼠主动脉张力（P < 0.01）。静脉推注肾上腺紧张素（2.5 nmol/kg，静脉注射）使麻醉大鼠的平均动脉压升高28%（P < 0.01）。1×10^(-7)mol/L肾上腺紧张素使培养的大鼠血管平滑肌细胞中的3H - 胸腺嘧啶核苷掺入量增加55%（P < 0.01）。肾上腺髓质素在不同程度上抑制肾上腺紧张素的这些活性。1×10^(-9)、1×10^(-8)和1×10^(-7)mol/L肾上腺紧张素分别使肾上腺髓质素释放率降低19%、35%和46%（P < 0.05或P < 0.01），且1×10^(-8)mol/L肾上腺髓质素也使大鼠主动脉的肾上腺紧张素释放抑制45%（P < 0.01）。
肾上腺紧张素是一种新型肽，可引发血管收缩、升压作用并诱导血管平滑肌细胞增殖。肾上腺紧张素与肾上腺髓质素在血管活性方面存在拮抗作用，在释放方面存在相互抑制。这些相互作用是前肾上腺髓质素（Pro - ADM）分子内调节的表现。
