Changes in plasma active renin and prorenin after endoscopic retrograde pancreatography

Plasma active renin, total renin (active renin plus prorenin) and immunoreactive trypsin were measured simultaneously before and after endoscopic retrograde pancreatography (ERP) in 9 subjects suspected of having pancreatic or biliary disease. After ERP, their plasma immunoreactive trypsin level increased significantly (p less than 0.02) from 12.4 +/- 1.5 to 163 +/- 57 ng/ml (means +/- SEM), while their plasma renin activity, total renin activity and ratio of active renin to total renin did not change. Individual values for the ratio of active renin to total renin correlated significantly (p less than 0.01) with those for immunoreactive trypsin in the basal condition (before ERP), but not after ERP. These results suggest that plasma trypsin is involved in activation of prorenin to active renin in the basal condition, and that ERP-induced increase in plasma trypsin has no effect on activation of prorenin.