Regulation of interdigestive contractions in the denervated stomach.

The effects of thiopental sodium on the regulation of interdigestive migrating contractions (IMC) in the stomach were investigated in dogs with extrinsically denervated fundic pouches. During the interdigestive state, strong phasic contractions in the pouch took place consistently in accordance with the IMC in the main stomach. The cyclic increase in plasma motilin concentration was more closely correlated with the increase in contractile activity in the pouch than the increase in the main stomach. General anesthesia by thiopental sodium promptly inhibited the IMC in the main stomach but the contractile activity in the pouch was not affected but gradually decreased in proportion to the decrease in plasma motilin concentration. In conclusion, contractile activity in the extrinsically denervated pouch, which is quite independent of the CNS, is directly controlled by a humoral factor(s), motilin. However, interdigestive motor activity in the extrinsically intact stomach appears to be regulated by the CNS as well as peripheral circulation humoral factors.