Analysis of the motor effects of gastrin and pentagastrin on the human alimentary tract in vitro.

Exogenous gastrin and its synthetic analogue pentagastrin (I.C.I. 50,123) stimulate the secretion of gastric juice in man (Makhlouf, McManus, and Card, 1964; Wormsley, Mahoney, and Ng, 1966), but little is known about their effect on human gastrointestinal muscle. It is not yet clear whether all parts ofthe alimentary tract are contracted by gastrin, or how closely the effects of the pentagastrin resemble those of the hormone itself. Nor is it known whether the motor effects of gastrin and pentagastrin in man are due to stimulation of intrinsic nerves or to a direct action on the smooth muscle cell. We have examined these problems by studying isolated strips of human gastrointestinal muscle.