Some physiological and pharmacological characteristics of the stimulus induced release of norepinephrine from the rabbit superior cervical ganglion

Abstract

The cervical sympathetic nerve stimulated release of norepinephrine (NE) from the rabbit superior cervical ganglion (SCG) was characterized. The quantity of NE released per impulse declined with increasing stimulation frequency over the range of 3/sec to 15/sec. Nerve stimulated NE release was potentiated by 1 micromolar desmethylimipramine and 25 micromolar phenoxybenzamine and inhibited by 1 micromolar bretylium, 25 micromolar methoxamine and 1 micromolar prostaglandin E₁. These results suggest that nerve stimulated NE release in the rabbit SCG occurs from sympathetic fibers which are subject to the same neuro-secretory control mechanisms as sympathetic fibers elsewhere in the autonomic nervous system.