| Abstract: | The ultrafiltrate of an aqueous extract of gluten depressed the peristaltic reflex of the rat isolated jejunum. Further purification increased the activity of the extract 200-fold. Biochemical analysis showed that this purified gluten ultrafiltrate contained over 50% of adenosine. Comparative studies of the effects of adenosine and crude gluten ultrafiltrate were carried out on various biological preparations in vitro and in vivo. Both substances depressed all preparations that contained smooth or cardiac muscle, adenosine being 200- to 1,000-times more active than gluten ultrafiltrate. Large doses of gluten ultrafiltrate were spasmogenic to guinea-pig isolated intestine; this was not found with adenosine. Neither substance had any demonstrable effect on striated muscle or on neuromuscular transmission. Both substances were inactivated by incubation with mammalian small intestinal mucosa and with purified adenosine deaminase. Therefore there seems little doubt that gluten ultrafiltrate owes its antiperistaltic action to its adenosine content. |
