Spasmolytic Action and Clinical Use of Glucagon

The inhibitory effect of glucagon on the motility of the gastrointestinal tract was first described by Stunkard et al. (1955) who noted inhibition of gastric hunger contractions in humans. The mechanism behind this effect could not be determined, but it was noted that it could be “independent of its effect on carbohydrate metabolism” since intravenous glucose injections failed to mimic the effect. Glucagon has since been found to have inhibitory action on the smooth muscle of many organs and species. Wingate and Pearce (1979) have compiled an extensive list of pertinent investigations focusing on the effects of glucagon on gastrointestinal motility, secretion, and absorption, and on blood flow (Table 1). Table 2 lists investigations in other areas in which glucagon has been found to have a similar smooth muscle relaxing effect.