Sympathetic Responses to Stress and Rilmenidine in 2K1C Rabbits. Evidence of Enhanced Nonvascular Effector Mechanism

摘要: We determined whether the sympathetic excitatory responses to environmental stressors and sympathoinhibitory rilmenidine are altered by renovascular hypertension. Rabbits were made hypertensive with a clip on right renal artery, left nerve recording electrode was implanted. After 3 or 6 weeks, animals given air-jet stress loud noise before after intravenous rilmenidine. Three weeks clipping, mean arterial pressure 28% 36% greater than preclip values. Air-jet elicited marked increase in activity, pressure, heart rate. Renal activity much rabbits, but pressor similar those observed normotensive animals. Acute administration of decreased blood more lesser inhibition activity. Rilmenidine markedly reduced increased during 3-week clipped rabbits extent other groups. These studies show that while enhanced they did not result responses, thus suggesting vascular neuroeffector mechanisms altered. By contrast, effects suggest contribution hypertension nervous system, one is caused an “nonvascular” mechanism. As such, agents such as very suitable effective for treatment