Influence of isoproterenol and propranolol on human intestinal transport in vivo.

We have studied the effects of a beta-adrenergic agonist and antagonist on transmucosal transport in the human jejunum and ileum in vivo. Using a triple lumen perfusion technique we have demonstrated that intravenous isoproterenol significantly increased absorption of sodium, chloride, and water in both the jejunum and ileum, and of potassium in the ileum. Beta blockade with intravenous propranolol significantly reduced jejunal electrolyte absorption and induced ileal water and sodium secretion. Isoproterenol reduced pressure wave activity in 6 of 8 subjects while propranolol was without any consistent motor effect. These results support a role for the beta-adrenergic division of the autonomic nervous system in the control of intestinal transport in humans.