Santos J C, Jerez S, Peral de Bruno M, Coviello A
Facultad de Ciencias Naturales e Instituto Miguel Lillo, INSIBIO, Fundación INELCO, Tucumán, Argentina.
Braz J Med Biol Res. 2000 Sep;33(9):1099-104. doi: 10.1590/s0100-879x2000000900018.
Angiotensin-(1-7) (Ang-(1-7)) increased osmotic water permeability in the isolated toad skin, a tissue with functional properties similar to those of the distal mammalian nephron. Concentrations of 0.1 to 10 microM were effective, with a peak at 20 min. This effect was similar in magnitude to that of frog skin angiotensin II (Ang II) and oxytocin but lower than that of human Ang II and arginine-vasotocin. The AT2 angiotensin receptor antagonist PD 123319 (1.0 microM) fully inhibited the response to 0.1 microM Ang-(1-7) but had no effect on the response to Ang II at the same concentration. The specific receptor antagonist of Ang-(1-7), A-779, was ineffective in blocking the response to Ang-(1-7) and to frog skin Ang II. The AT1 receptor subtype antagonist losartan, which blocked the response to frog skin Ang II, was ineffective in blocking the response to Ang-(1-7). The present results support the view of an antidiuretic action of Ang-(1-7) in the mammalian nephron.
血管紧张素 -（1 - 7）（Ang -（1 - 7））可增加离体蟾蜍皮肤的渗透水通透性，蟾蜍皮肤是一种功能特性与哺乳动物远端肾单位相似的组织。浓度为0.1至10微摩尔时有效，在20分钟时达到峰值。该效应的强度与蛙皮血管紧张素II（Ang II）和催产素相似，但低于人Ang II和精氨酸 - 血管收缩素。AT2血管紧张素受体拮抗剂PD 123319（1.0微摩尔）完全抑制了对0.1微摩尔Ang -（1 - 7）的反应，但对相同浓度下Ang II的反应无影响。Ang -（1 - 7）的特异性受体拮抗剂A - 779在阻断对Ang -（1 - 7）和蛙皮Ang II的反应方面无效。AT1受体亚型拮抗剂氯沙坦可阻断对蛙皮Ang II的反应，但在阻断对Ang -（1 - 7）的反应方面无效。目前的结果支持Ang -（1 - 7）在哺乳动物肾单位中具有抗利尿作用的观点。
