Liard J F
J Cardiovasc Pharmacol. 1986;8 Suppl 7:S61-5. doi: 10.1097/00005344-198600087-00012.
We first discuss the question of direct versus indirect mechanisms in the vasoconstrictor effects induced by low plasma levels of arginine vasopressin (AVP). By infusing AVP directly into the arteries supplying various organs and tissues and measuring regional blood flows with radioactive microspheres in conscious dogs, it was determined that the increase in resistance measured after systemic administration of small amounts of AVP in the skeletal muscle, small intestine, colon, and abdominal fat results in large part from indirect mechanisms. Direct vasoconstrictor effects of AVP at these plasma concentrations were limited to the skin, the pancreas, and the compact bones. We then consider the question of cardiovascular effects of AVP from its antidiuretic activity. In the presence of a vascular antagonist, AVP decreased peripheral resistance and increased cardiac output in conscious dogs. An analog with selective antidiuretic activity, VDAVP, produced the same effects as the combination of vasopressin plus vascular antagonist. These data indicate that vasopressin, by its antidiuretic activity, produces cardiovascular effects that are opposed to many of those produced by its vasoconstrictor action. Studies in 48-h dehydrated dogs showed that part of the hemodynamic response to blockade of the vasoconstrictor action of vasopressin under these conditions is caused by unmasking cardiovascular effects linked to the antidiuretic activity of the arginine vasopressin molecule.
我们首先讨论低血浆水平精氨酸加压素（AVP）诱导的血管收缩效应中的直接机制与间接机制问题。通过将AVP直接注入供应各种器官和组织的动脉，并使用放射性微球在清醒犬中测量局部血流量，确定在骨骼肌、小肠、结肠和腹部脂肪中，全身给予少量AVP后测得的阻力增加在很大程度上源于间接机制。在这些血浆浓度下，AVP的直接血管收缩效应仅限于皮肤、胰腺和密质骨。然后，我们考虑AVP抗利尿活性所产生的心血管效应问题。在存在血管拮抗剂的情况下，AVP降低清醒犬的外周阻力并增加心输出量。具有选择性抗利尿活性的类似物VDAVP产生的效果与加压素加血管拮抗剂的组合相同。这些数据表明，加压素通过其抗利尿活性产生的心血管效应与其血管收缩作用产生的许多效应相反。对48小时脱水犬的研究表明，在这些条件下，对加压素血管收缩作用阻断的部分血流动力学反应是由于揭示了与精氨酸加压素分子抗利尿活性相关的心血管效应。
