RESUMO
Thirty-three experiments were made on mongrel dogs operated on according to Basov, with the use of phentolamine, pilocarpine, atropine, histamine and their combinations. It was established that administration of histamine gives rise to an increase in gastric secretion, provided the animals are pretreated with phentolamine or with combined pilocarpine and phentolamine. Histamine-induced gastric secretion considerably decreases, provided the animals are pretreated with atropine and ceases almost completely after administration of combined atropine and phentolamine. It is concluded that the stimulating effect of phentolamine on gastric secretion is caused by an increase in the sensitivity of H2-receptors and cholinoreceptors under blockade of the alpha-adrenoreactive systems.
Assuntos
Mucosa Gástrica/efeitos dos fármacos , Fentolamina/farmacologia , Animais , Atropina/farmacologia , Cães , Mucosa Gástrica/metabolismo , Histamina/farmacologia , Pilocarpina/farmacologia , Tempo de Reação/efeitos dos fármacos , Receptores Adrenérgicos alfa/efeitos dos fármacos , Receptores Histamínicos H2/efeitos dos fármacosRESUMO
The effects of phentolamine and propranolol in doses 2.5 mg/kg on histamine gastric secretion were examined in dogs operated on according to the V. A. Basov's method. It was ascertained that phentolamine raised the secretion rate by 2.6 times, the hourly output of hydrochloric acid by 4.4 times, secretion of pepsin and chlorides by 2.5 times. Propranolol did not affect gastric secretion. Administration of phentolamine in a dose of 0.025 mg/kg three times a day for 10 days ta patients with a moderately pronounced atrophic gastritis increased the secretion rate and pepsin secretion by 1.8 times. The hourly output of hydrochloric acid rose by 2.8 times.
