Rebound rise in renin concentrations after cessation of salicylates.

Salicylates are widely used in the treatment of rheumatic disorders, and they have been shown to induce minor changes in renal function. One of the major mechanisms of action of salicylates is the suppression of prostaglandin synthetase activity, and in animal rnodels renal prostaglandin production is closely related to renin release and the regulation of renal blood flow. Indomethacin has been shown to decrease the glomerular filtration rate and to lower plasma renin activity in human beings, and to reduce the antihypertensive effectiveness of certain beta-adrenoreceptor-blocking agents. We therefore studied the effects of aspirin, another commonly prescribed non-steroidal antiinflammatory agent, on plasma renin concentration, both during administration and after withdrawal.