Effect of Acidosis and Prostaglandin $E_1$ upon Acid Secretion in Isolated Whole Stomach in Rat

흰쥐의 적출한 위(胃)에서 산증(酸症)과 Prostaglandin $E_1$이 위산(胃酸) 분비에 미치는 영향

This study was undertaken to investigate the effect of the acidosis on the gastric acid secretion in the isolated whole stomach of the rat and the effect of prostaglandin $E_1$ on the gastric acid secretion influenced by the acidosis. Twenty-two male albino rats(Sprague-Dawley strain) were used. The isolated whole stomach from each rat was introduced into the Kreb's solution which was continuously gassed with $95%O_2-5%CO_2$ for 1 hour, after irrigation of the lumen with cold physiological saline$(4^{\circ}C)$. Thereafter, each stomach was irrigated again with 5% dextrose solution (pH 7.4, $37^{\circ}C$), and filled with the dextrose solution. All the stomachs with the dextrose solution were divided into 4 groups according to the Kreb's solutions in which each stomach was incubated for 30 min: 1) control group, in the pH 7.4 solution, 2) $PGE_1$ group, in the pH 7.4 solution containing $5\;{\mu}g/ml$ of $PGE_1$, 3) acid group, in the pH 7.0 solution, and 4) $acid+PGE_1$ group, in the pH 7.0 solution containing $5\;{\mu}g/ml$ of $PGE_1$. After incubatory period, the contents of each stomach were collected and centrifuged(1,500 rpm, room temperature) for 15 min. The acid output in the supernatant was determined with 0.012 N NaOH by means of autotitrator(Dosimat, Metrohm Herisau Co.) at pH 7.4. Results obtained were as follows: 1) The acid output of the acid group increased significantly in comparison with the control value. 2) The acid output of the $acid+PGE_1$ group decreased significantly in comparison with the acid group. It is inferred from the above results that the acidosis facilitates the gastric acid secretion and $PGE_1$ inhibits the gastric acid secretion induced by the acidosis.