Russ R D, Brizzee B L, Walker B R
Department of Physiology, University of New Mexico School of Medicine, Albuquerque 87131.
Am J Physiol. 1992 Jan;262(1 Pt 2):R25-32. doi: 10.1152/ajpregu.1992.262.1.R25.
Experiments were performed in conscious chronically instrumented rats to determine the role of arginine vasopressin (AVP) in the cardiovascular adjustments to acute and chronic increases in plasma osmolality. Animals were implanted with pulsed Doppler flow probes and arterial and venous catheters for the determination of cardiac output, mean arterial blood pressure (MABP), and heart rate and for the calculation of total peripheral resistance and baroreflex sensitivity (BRS). Before and after raising plasma osmolality by either 48-h water deprivation or acute hypertonic saline infusion, specific V1- or V2-vasopressinergic receptor antagonists or vehicle were administered to the animals, and the cardiovascular responses were noted. MABP was significantly elevated in water-deprived animals. These animals also exhibited significantly increased BRS, which was further increased by administration of the V1-receptor antagonist. Animals subjected to acute hypertonic saline infusion also demonstrated increased MABP, although the infusion, unlike water deprivation, did not affect BRS. We observed no significant effects on any other variable measured. We conclude that AVP plays a relatively minor role in the cardiovascular adjustments to acute and chronic hyperosmolality.
在清醒的慢性植入仪器的大鼠身上进行实验，以确定精氨酸加压素（AVP）在心血管系统对急性和慢性血浆渗透压升高的调节中的作用。给动物植入脉冲多普勒血流探头以及动脉和静脉导管，用于测定心输出量、平均动脉血压（MABP）和心率，并计算总外周阻力和压力反射敏感性（BRS）。通过48小时禁水或急性输注高渗盐水使血浆渗透压升高之前和之后，给动物施用特异性V1或V2血管加压素能受体拮抗剂或赋形剂，并记录心血管反应。禁水动物的MABP显著升高。这些动物的BRS也显著增加，施用V1受体拮抗剂后进一步增加。急性输注高渗盐水的动物也表现出MABP升高，尽管与禁水不同，输注不影响BRS。我们观察到对所测量的任何其他变量均无显著影响。我们得出结论，AVP在心血管系统对急性和慢性高渗状态的调节中起相对较小的作用。
