The renin--kallikrein--prostaglandin system: plasma active and inactive renin and urinary kallikrein during prostacyclin infusion in man.

Renal prostaglandins are integrated with the kallikrein-kinin and renin-angiotension systems in a vasoactive hormone complex. Prostacyclin potently stimulates renin release from rabbit cortical slices and plasma renin activity rises in response to prostacyclin infusion in man. Prostaglandins also stimulate the production of kallikrein, a potential activator of renin in vivo. To investigate the mechanism of prostacyclin induced renin release, human volunteers were infused with prostacyclin 8ngKg-1min-1 and vehicle alone in random order. Despite a marked increase in plasma active renin during prostacyclin both plasma inactive renin and urinary kallikrein failed to alter from control values. Urinary sodium and volume were increased by prostacyclin. The stimulation of renin by intravenous prostacyclin is not mediated by activation of the kallikrein system.