Parkes D G, Coghlan J P, McDougall J G, Scoggins B A
Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Australia.
Am J Physiol. 1988 Apr;254(4 Pt 2):H811-5. doi: 10.1152/ajpheart.1988.254.4.H811.
The hemodynamic and metabolic effects of long-term (5 day) infusion of human atrial natriuretic factor (ANF) were examined in conscious chronically instrumented sheep. Infusion of ANF at 20 micrograms/h, a rate below the threshold for an acute natriuretic effect, decreased blood pressure by 9 +/- 1 mmHg on day 5, associated with a fall in calculated total peripheral resistance. On day 1, ANF reduced cardiac output, stroke volume, and blood volume, effects that were associated with an increase in heart rate and calculated total peripheral resistance and a small decrease in blood pressure. On days 4 and 5 there was a small increase in urine volume and sodium excretion. On day 5 an increase in water intake and body weight was observed. No change was seen in plasma concentrations of renin, arginine vasopressin, glucose, adrenocorticotropic hormone, or protein. This study suggests that the short-term hypotensive effect of ANF results from a reduction in cardiac output associated with a fall in both stroke volume and effective blood volume. However, after 5 days of infusion, ANF lowers blood pressure via a reduction in total peripheral resistance.
在清醒的、长期植入仪器的绵羊身上，研究了长期（5天）输注人心房利钠因子（ANF）对血流动力学和代谢的影响。以20微克/小时的速率输注ANF，该速率低于急性利钠效应的阈值，在第5天时血压降低了9±1毫米汞柱，同时计算得出的总外周阻力下降。在第1天，ANF降低了心输出量、每搏输出量和血容量，这些效应与心率增加、计算得出的总外周阻力增加以及血压略有下降有关。在第4天和第5天，尿量和钠排泄量略有增加。在第5天，观察到水摄入量和体重增加。血浆肾素、精氨酸加压素、葡萄糖、促肾上腺皮质激素或蛋白质的浓度未见变化。这项研究表明，ANF的短期降压作用是由于心输出量减少，同时伴有每搏输出量和有效血容量下降。然而，输注5天后，ANF通过降低总外周阻力来降低血压。
