Nine groups of experiments were conducted on 120 rats and 55 dogs to study the morphological changes and the density of cholinergic nerve fibres in the intramural nerve apparatus of the stomach after cooling of the vagus nerves at various temperatures and time regimens of the exposure (-35-45 degrees, -70-80 degrees for 2-3 sec., 15 sec in one, two, and three exposures). The completeness of vagotomy was determined by the method of parietal pH measurement and modelling of stress-induced ulcers. It was established that depending on the thickness of the nerves and the regimen of the exposure to cooling, one can achieve total vagotomy with destructive changes in the nerve apparatus, incomplete vagotomy and transient inhibition-blockade of the acid-regulating function of vagus nerves with maintenance of the morphological and histochemical characteristics of intramural plexuses.