Abstract
Plasma somatostatin levels were measured by radioimmunoassay (RIA) at various times after rapid injection into the blood of 4 patients with acromegaly, 4 patients with hepatic failure, and 4 healthy subjects. In contrast to the single peak found in normal and acromegalic individuals, two distinct peaks were observed in each patient with liver failure. The first occurred at about the same time as that observed in the other two groups, but the second occurred about 3 min later. This second peak could not be distinguished immunologically from the intact somatostatin tetradecapeptide. The half-time disappearance of somatostatin in patients with hepatic failure was significantly longer than in the normal subjects. Acromegalic subjects tended to have the shortest half-time disappearance of the injected somatostatin and the highest peak level. The results are consistent with the possibility that altered metabolism and/or binding of somatostatin occurs in hepatic failure and in acromegaly.