Article: article from journal or magazin.
Alpha 1-adrenoceptor blockade in renal hypertensive rats with low and high renin levels
American Journal of Physiology. Heart and Circulatory Physiology
4 Pt 2
Journal Article Research Support, Non-U.S. Gov't --- Old month value: Apr
A total of 75 male Wistar rats with one-kidney, one-clip renal hypertension was maintained on either a regular (RNa) or a low-salt (LNa) diet for 3 wk after clipping. Blood pressure in the unanesthetized rats was equally elevated independent of sodium intake. Plasma renin activity was higher in LNa animals, and blood pressure was renin dependent only in this group, as evidenced by the blood pressure response to 10 mg/kg captopril iv. There was no significant difference in plasma catecholamines between RNa and LNa rats, although in the former the sympathetic nervous system is believed to play a major role in sustaining high blood pressure. The acute intravenous administration of 0.5 mg/kg prazosin did not induce a more pronounced blood pressure fall in the RNa rats. Prazosin enhanced plasma norepinephrine levels similarly in both groups, but epinephrine levels only rose in the LNa animals. Prazosin also markedly stimulated plasma renin activity rendering blood pressure renin dependent even in RNa rats. Thus, using alpha 1-adrenoceptor blockade, it has not been possible to demonstrate that the blood pressure elevation of salt-repleted one-kidney, one-clip renal hypertensive rats is due to an enhanced sympathetic nerve activity. Data obtained with sympatholytic agents must be interpreted with great caution if renin activity cannot be kept unchanged.
Animals Blood Pressure Captopril/pharmacology Diet, Sodium-Restricted Heart Rate Hypertension, Renal/*metabolism Male Norepinephrine/blood Prazosin/pharmacology Rats Rats, Inbred Strains Receptors, Adrenergic, alpha/*drug effects Renin/*blood
Web of science
Last modification date