Abstract

Adrenalectomy produces many changes in gastric functional parameters including gastric acid secretion, gastric motility and mucosal blood flow. The present study was undertaken to assess the effect of acute bilateral adrenalectomy and reserpine on gastric mucus secretion and degradation in the pyloric ligated rats. Groups of Wistar rats of mixed sexes were adrenalectomized or administered with 5 mg/kg reserpine intraperitoneally or given both treatment followed by pyloric ligation. Adherent mucus was assessed by the alcian blue binding technique while erosion of the surface gel was assessed from the appearance of sialic acids and galactose in the gastric juice. Gastric mucosa injury was quantified by measuring the area of gastric mucosa damage. The amount of alcian blue bound to adherent mucus and soluble mucin concentration were not significantly affected by adrenalectomy (P > 0.05). Reserpine diminished adherent mucus secretion and increased soluble glycoprotein in the gastric juice. Adrenalectomized animals (40%, n = 5) developed haemorrhagic lesions as compared to 100% (n = 5) in animals treated with reserpine. Adrenalectomy or propranolol did not protect the animals against the reserpine induced injury. It is concluded that the adrenal glands seem to be of no importance in the secretion of gastric mucus but reserpine inhibits mucus release and stimulates surface mucus gel breakdown via β-adrenoceptor stimulation.

Key words: Adrenalectomy, gastric mucus, reserpine, sialic acid.