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

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 phenoxylbenzamine 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 neurosecretory control mechanisms as sympathetic fibers elsewhere in the autonomic nervous system.