“…A number of authors have observed that gastric acid secretion, stimulated by food, 2-deoxyglucose, histamine or gastrin, is inhibited by prostaglandin E1 (PGE1), both in vivo (Robert, Nezamis & Phillips, 1967, 1968Lippman, 1968;Shaw & Ramwell, 1968;Jacobson, 1970 and Nezamis, Robert & Stowe, 1971) and in vitro (Way & Durbin, 1969) and it is tempting to postulate that such inhibition is the result of the feed-back mechanism envisaged above.…”