[Relationship between the frequencies of pacemaker and action potentials in the duodenal smooth muscle of dogs].

In dogs with electrodes indwelled into the duodenum, four phases of the change of duodenum pacesetter potentials were revealed at rest in hunger whereas no such changes were observed during digestion. The frequency ranges of both the pacesetter potentials and the bursts of action potentials were wider in hunger than during digestion. Without the digestive activity, the periodicity of the frequency oscillations of the pacemaker potentials corresponded with the periodicity of action potentials, whereas during the process of digestion the constancy of the pacesetter potential frequency corresponded with the action potential constancy. The regularities of optimal conditions for action potentials of the duodenum smooth muscles are discussed as well as the methodological conditions for revealing the authentic character of changes in the pacesetter potential frequency.