Vasoactive substances in early dumping syndrome: effects of dumping provocation with and without octreotide.

ABSTRACT

In patients after gastric surgery, early dumping symptoms can be provoked by oral glucose challenge. Octreotide effectively prevents the occurrence of dumping symptoms. We have studied plasma renin activity (PRA), aldosterone and atrial natriuretic peptide (ANP) concentrations in nine patients with early dumping, 10 surgical control subjects and nine healthy control subjects after an oral glucose challenge preceded by either placebo or 25 micrograms of octreotide subcutaneously (s.c.). In the dumping group, basal PRA was significantly (P < 0.01) higher (3.9 +/- 0.6 micrograms L-1 h-1) than in either surgical or healthy control subjects (1.1 +/- 0.3 micrograms L-1 h-1 and 1.1 +/- 0.2 micrograms L-1 h-1 respectively) and showed a significant rise after glucose ingestion to 5.4 +/- 0.9 micrograms L-1 h-1 that did not occur in control subjects. Aldosterone concentration showed a concomitant rise. In dumping patients, plasma ANP decreased after glucose ingestion from 31 +/- 6 ngL-1 to 21 +/- 5 ngL-1 (P < 0.05). This decrease did not occur in control subjects. Early dumping is associated with an activation of the renin-aldosterone axis and a decrease in plasma ANP, reflecting a hypovolaemic state. Octreotide prevents the occurrence of these changes.