High sugar intake via the renin-angiotensin system blunts the baroreceptor reflex in adult rats that were perinatally depleted of taurine

摘要

Perinatal taurine depletion leads to several physiological impairments in adult life, in part, due to taurine’s effects on the renin-angiotensin system, a crucial regulator of growth and differentiation during early life. The present study tests the hypothesis that perinatal taurine depletion predisposes adult female rats to impaired baroreceptor control of arterial pressure by altering the renin-angiotensin system. Female Sprague Dawley (SD) rats were fed normal rat chow and from conception to weaning drank 3% beta-alanine in water (taurine depletion, TD) or water alone (Control, C). Female offspring ate a normal rat chow and drank water with (G) or without (W) 5% glucose throughout the experiment. To test the possible role of the renin-angiotensin system, 50% of the rats received captopril (an angiotensin converting enzyme inhibitor, 400 mg/L) from 7 days before parameter measurements until the end of experiment. At 7-8 weeks of age, arterial pressure, heart rate, baroreflex control of heart rate and renal nerve activity were studied in either conscious, freely moving or anesthetized rats. Perinatal taurine depletion did not alter resting mean arterial pressure or heart rate in the adult female offspring that received either high or normal sugar intake. Captopril treatment slightly decreased mean arterial pressure but not heart rate in all groups. Compared to controls, only the TDG rats displayed blunted baroreflex responses. Captopril treatment normalized baroreflex sensitivity in TDG. The present data indicate that in perinatal taurine depleted female rats, the renin-angiotensin system underlines the ability of high sugar intake to blunt baroreceptor responses.