Gastric motility is stimulated but overall blood flow is unaffected during cold restraint in the rat.

The relationship between cold restraint-induced lesion formation, gastric motility, and gastric mucosal blood flow was studied in rats. Both anesthetized and unanesthetized animals placed in cold restraint developed gastric mucosal lesions. Gastric (corpus) motility was measured using extraluminal force transducers. Animals placed in cold restraint developed persistent, high amplitude, prolonged duration contractions. Those rats in which such contractions lasted greater than 1 h developed gastric mucosal lesions, whereas those animals in which such contractions lasted less than or equal to 1 h had no lesions. Overall gastric mucosal blood flow was measured using the hydrogen gas clearance technique. There was no significant change in overall gastric mucosal blood flow measured after 1, 2, and 3 h of cold restraint. We conclude that (a) the physical effect of cold water immersion is by itself sufficient to cause cold "restraint" lesions and (b) such lesions are associated with high amplitude, prolonged duration contractions lasting greater than 1 h.