AGE-RELATED-CHANGES IN GASTRIC-MUCOSAL BICARBONATE SECRETION IN RATS

The present study was designed to examine the effects of aging on gast ric bicarbonate secretion, a major mucosal defensive factor, basally a nd after treatment with 16,16-dimethyl-prostaglandin (PC) E(2), a know n stimulant of gastric bicarbonate secretion, Our data have demonstrat ed that aging was associated with significant decline in basal gastric bicarbonate secretion (as reflected by luminal pH and bicarbonate out put). While 16,16-dimethyl-PGE(2) significantly stimulated both lumina l pH and bicarbonate output in 3-month-old and 1-year-old rats; no sig nificant changes in either luminal pH or bicarbonate output were noted in the 2-year-old rats after treatment with 16,16-dimethyl-PGE(2). In summary, aging was associated with significantly lower gastric lumina l pH and bicarbonate output in the rat stomach, and aging also blunted the PC-mediated increases in gastric bicarbonate secretion in the rat .