Mechanism of impaired baroreflex control in prehypertensive Dahl salt-sensitive rats.

摘要: Dahl salt-sensitive rats fed a low salt diet demonstrate functional impairment in baroreflex control of cardiovascular function prior to the development hypertension. The purpose this study was identify mechanism(s) responsible for impaired prehypertensive rats. To examine central and efferent portions arc, we electrically stimulated aortic depressor nerve urethane anesthetized salt-resistant while recording arterial pressure, heart rate, sympathetic activity. Aortic stimulation produced equivalent responses both groups, indicating that mechanisms could not account impairment. In separate groups rats, multifiber afferent baroreceptor discharge recorded pressure increased with phenylephrine. Prehypertensive demonstrated significantly less activation than is mechanism abnormalities. arch distensibility different between strains, suggesting probably due abnormalities vessel wall distensibility. Since strains normotensive range did differ appears be primary defect rather being secondary We speculate any elevation may contribute rat's genetic propensity develop