The influence of a parasympathetic agonist and antagonist on human intestinal transport in vivo.

We studied the influence of parasympathetic stimulation and blockade on transmucosal transport in the human jejunum and ileum in vivo. Using a triple lumen tube perfusion technique, we observed that intravenous administration of neostigmine caused a significant change from absorption to secretion of sodium chloride and water in the jejunum. Similar but not statistically significant changes were observed in the ileum. Intravenous atropine significantly enhanced absorption of chloride in the jejunum and of sodium, chloride, and water in the ileum. Intraluminally administered neostigmine or atropine did not influence transport in either jejunum or ileum. Intraluminal pressure wave activity recorded synchronously with the transport studies was also influenced by these drugs, but there were either no correlations or poor correlations between their effects on transport and motor activity. In addition, intraluminally administered drugs caused similar motor responses but did not influence transport. It appears unlikely therefore that the changes observed in transport were secondary to the changes in motility. It is concluded that cholinergic and anticholinergic drugs influence salt and water transport in the human small intestine in vivo, and these responses support the possibility of a role for the parasympathetic nervous system in the control of intestinal transport.