FURTHER STUDIES ON THE MODE OF ACTION OF ISOPRENALINE ON GASTRIC SECRETION IN THE CONSCIOUS RAT

Abstract
1 The effect of isoprenaline on gastric secretion evoked by various means has been studied in conscious rats provided with Pavlov and Heidenhain pouches. 2 Interdigestive acid secretion in the Pavlov pouch was reduced by isoprenaline, whereas pepsin secretion was unaltered. 3 Central vagal stimulation effected by 2-deoxy-d-glucose injection evoked a gastric secretory response that was substantially reduced by isoprenaline. 4 2-Deoxy-d-glucose increased the mobilization of gastric mucosal histamine, an effect that was prevented by isoprenaline. 5 Isoprenaline infusion alone induced a slight increase in histamine mobilization and also a considerable elevation of immunoreactive serum gastrin concentration. 6 The secretory response to food in the Pavlov pouch was almost abolished by isoprenaline. 7 Although the acid response to histamine in the Heidenhain pouch was susceptible to isoprenaline inhibition, that to methacholine was not. 8 Pepsin secretion in the Heidenhain pouch preparation stimulated by histamine or methacholine seemed to be enhanced by isoprenaline.