Parkes D G, Coghlan J P, McDougall J G, Tyers M R, Scoggins B A
Howard Florey Institute of Experimental Physiology and Medicine, Parkville, Australia.
Clin Exp Hypertens A. 1990;12(3):383-98. doi: 10.3109/10641969009074741.
The hemodynamic effects of short-term infusion of atrial natriuretic factor (ANF) were observed in sheep with combined alpha/beta adrenoceptor pharmacological blockade. The effect of ANF on the sympathetically-mediated baroreflex system was observed in conscious sheep in which aortic and vena caval balloon occluders had been surgically implanted. ANF infused at 100 micrograms/h for 60 min produced similar effects on blood pressure, cardiac output and stroke volume during alpha/beta-adrenoceptor blockade, compared to the responses seen in normal sheep, however the increases in heart rate and total peripheral resistance were reduced. ANF markedly enhanced the gain of the baroreceptor-heart rate reflex in the sheep. This effect may mediate the large increase in heart rate which is associated with a small fall in blood pressure during short-term infusion of ANF. In conclusion, the sympathetic nervous system plays an important role in regulating the reflex cardiovascular responses to short-term infusion of ANF in sheep. The large species variation in the hemodynamic responses to ANF may be related to differing degrees of stimulation or inhibition of the baroreceptor system to affect heart rate and/or peripheral resistance.
在α/β肾上腺素能受体药理学阻断的绵羊中观察了心房利钠因子（ANF）短期输注的血流动力学效应。在已手术植入主动脉和腔静脉球囊阻塞器的清醒绵羊中观察了ANF对交感神经介导的压力反射系统的影响。与正常绵羊的反应相比，在α/β肾上腺素能受体阻断期间，以100微克/小时的速度输注ANF 60分钟对血压、心输出量和每搏量产生了类似的影响，然而心率和总外周阻力的增加有所减少。ANF显著增强了绵羊压力感受器-心率反射的增益。这种效应可能介导了在短期输注ANF期间与血压小幅下降相关的心率大幅增加。总之，交感神经系统在调节绵羊对短期输注ANF的反射性心血管反应中起重要作用。对ANF的血流动力学反应的巨大物种差异可能与压力感受器系统的不同程度的刺激或抑制有关，从而影响心率和/或外周阻力。
