Effects of Intravenous Catecholamine on Gastric Acid, Gastrin and Secretin Secretion in Basal State of the Rat

정맥 주입한 Catecholamine이 흰쥐의 기초상태시 위산, Gastrin 및 Secretin 분비에 미치는 영향

This study was conducted to investigate the effects of epinephrine and norepinephrine on basal gastric acid secretion and plasma gastrin and secretin concentration in the conscious rat. One hundred and eighty-four albino rats with gastric cannula were used after 18 hours or more of fast, with water ad libitum. In a restraint cage for collection of gastric juice, physiological saline (0.9% NaCl) was continuously infused into the jugular vein through a catheter for one hour at a rate of 1 ml/hr (control period). Immediately after the control period, epinephrine (1, 2, 4, 8 and $16{\mu}g/ml/hr)$, norepinephrine (1, 2, 4, 8 and $16{\mu}g/ml/hr)$ or physiological saline (1 ml/hr) was infused for another one hour. Gastric juice was collected at one hour interval for two hours infusion period. Adrenergic antagonists, phentolamine and propranolol were injected into the jugular vein 5 min prior to the infusion of epinephrine or norepinephrine at a dose of 0.2 mg/0.1 ml. Blood was sampled from the jugular vein for the radioimmunoassay of plasma gastrin and secretin after the collection of gastric juice. The results were as follows: 1) Both epinephrine and norephinephrine significantly increased gastric acid output in a dosedependent manner. 2) The effects of epinephrine and norepinephrine on the gastric acid secretion were antagonized by the pretreatment with phentolamine and propranolol. 3) Plasma gastrin and secretin concentrations were not significantly affected by the intravenous infusion of epinephrine and norepinephrine. It can be inferred from the above results that epinephrine and norepinephrine facilitate gastric acid secretion in conscious rats and the mechanism of which is attributed to ${\alpha}\;and\;{\beta}$ adrenergic receptors rather than gastrin and secretin.