Inhibition of gastric electrical and mechanical activity by intraduodenal agents in pigs and the effects of vagotomy.

Miniature pigs were chronically implanted with gastric electrodes, strain gauge devices allowing the measurement of circular contractions in the antrum and body of the stomach, and with a duodenal catheter through which duodenal infusions were administered. Inhibition of gastric motility by intraduodenal agents was measured before and after truncal vagotomy in conscious animals 20 min after feeding of a normal meal. The agents infused in the duodenum (10 ml/min, 4 min), were: HCl 75 mEq/l(A), glucose 100 g/l(G), olive oil 10% pH 7(L), amino acids (AA) and saline. Before vagotomy, motor activity during the first 5 min was inhibited 50-80% with respect to basal levels; the duration of action was G No. L greater than A; AA had very little effect, and saline no effect. Inhibition was on the whole similar in the antrum and gastric body. After vagotomy, the inhibitory effect of A was reduced from 80 to 20% in the antrum, and completely suppressed in the gastric body. Inhibitory effects of G and L were completely suppressed.