The Effects of Captopril, Propranolol, and Indomethacin on Blood Pressure and Plasma Renin Activity in Spontaneously Hypertensive and Normotensive Rats

Summary Captopril reduced blood pressure and increased PRA in both SHR and NTR. Both propranolol and indomethacin caused significant reductions in resting PRA of both SHR and NTR but only propranolol caused an inhibition of the PRA changes caused by captopril. Furthermore, since propranolol was highly effective only in SHR and captopril decreased blood pressure much more in SHR than NTR, the increase in PRA caused by captopril in SHR was probably reflexly mediated by compensatory sympathetic activation, all of which actions were a consequence of reducing angiotensin II formation.