Pharmacological evidence for active reflex dilatation

Abstract

Pharmacological evidence for the existence of active reflex dilatation has been obtained by the use of agents which prevent the release of norepinephrine. Similar conclusions have been reached using an amine oxidase inhibitor to slow the rate of degradation of norepinephrine. The contribution of the active and passive components to the total reflex dilatation has been assessed. It is concluded that active reflex dilatation occurs in response to the intravenous injection of epinephrine or norepinephrine and that the reflex may be principally active even when a high level of sympathetic tone exists.