Local effects of 16, 16-dimethyl prostaglandin E2 on gastric blood flow and acid secretion.
The effects of luminal administration of 16, 16-dimethyl PGE2 on gastric blood flow and histamine-stimulated acid secretion were determined in a double-chambered preparation of canine fundic stomach. This model permitted simultaneous assessment of two segments of mucosa (17 cm2 each), one control and the other test, supplied by the same vascular pedicle. Topical application of 25 microgram 16, 16-dimethyl PGE2 in 15 ml HCl to the test chamber significantly increased mucosal blood flow of the test chamber from 1.2 +/- 0.1 to 2.5 +/- 0.5 ml/min (P less than 0.05) whereas no significant change in mucosal blood flow was noted in the control mucosa. Intravenous infusion of histamine at 1.0 microgram/kg/min stimulated comparable amounts of acid secretion in both segments of mucosa. The addition of 16, 16-dimethyl PGE2 (25 microgram in 15 ml of HCl) in the bathing solution of the test chamber significantly reduced histamine-stimulated acid secretion from 22.5 +/- 3.1 to 8.4 +/- 1.2 microEq/min (P less than 0.01) in the test mucosa whereas the control mucosa showed no evidence of secretory inhibition throughout the experiment. Since the control mucosa was supplied by the same vascular pedicle as the test mucosa, we concluded that the observed vasodilating and antisecretory effects of luminal administration of 16, 16-dimethyl PGE2 were local rather than systemic effects following its absorption from the stomach.
D015064:16,16-Dimethylprostaglandin E2 / Q000494:pharmacology*; D000287:Administration, Topical; D000818:Animals; D001775:Blood Circulation / Q000187:drug effects; D004285:Dogs; D005750:Gastric Juice / Q000187:drug effects* / Q000378:metabolism; D011459:Prostaglandins E, Synthetic / Q000494:pharmacology*; D013270:Stomach / Q000098:blood supply / Q000187:drug effects*
D011459:Prostaglandins E, Synthetic; D015064:16,16-Dimethylprostaglandin E2