Abstract
It is well known that reserpine causes a depletion of catecholamine and 5-hydroxytryptamine contents in various organs and tissues thereby preventing sympathetic transmission (1, 2). In order to eliminate sympathetic effects on gastro-intestinal motility, reserpine has usually been given to animals for a few days or at least 20 hr before experiment (3-5). One disadvantage of these experiments is that observation of a control response to stimulation of the sympathetic nerve cannot be done.
Recently it has been observed that reserpine added to bathing solution was effective in reducing or abolishing the sympathetically induced response of isolated preparations (6-8). In these experiments, it has been presumed that mechanisms other than an overall depletion of catecholamine contents possibly accounted for the acute inhibitory action of reserpine.
The present experiment was made to elucidate whether or not an acute effect of reserpine can be demonstrated on the sympathetically induced response of the dog stomach in vivo. Theresult showed that a single large dose of reserpine injected intravenously inhibited selectively the sympathetic nerve response within 4-5 hr.
