title: Central sympathetic control of spinal endothelin release in the rat.
abstract: Endothelin and its receptors have been identified in the spinal cord. Intrathecal administration of endothelin-3 produces hypotension in anesthetized rats. The present study was designed to identify whether endothelin-3 is released upon changes in sympathetic nervous activity. Endothelin-3-like immunoreactivity in spinal superfusates was directly correlated with resting arterial pressure. Endothelin-3 levels were enhanced by hypothalamic stimulation and by hemorrhage-induced hypotension and reduced by nitroprusside-induced hypotension. These findings suggest that sympathetic activation enhances endothelin-3 release but that nitroprusside may act directly to suppress release. We propose that endothelin-3 plays a role in spinal regulation of sympathetic outflow.
authors.affiliation: Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, MO 63104.
authors.forename: M M
authors.initials: MM
authors.lastname: Knuepfer
authors.forename: D
authors.initials: D
authors.lastname: O'Brien
authors.forename: D
authors.initials: D
authors.lastname: Hoang
authors.forename: Q
authors.initials: Q
authors.lastname: Gan
authors.forename: C
authors.initials: C
authors.lastname: Song
mesh_terms: D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004558:Electric Stimulation; D016232:Endothelins / Q000378:metabolism*; D007031:Hypothalamus / Q000502:physiology; D007278:Injections, Spinal; D008297:Male; D009599:Nitroprusside / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000187:drug effects / Q000378:metabolism*; D013564:Sympathetic Nervous System / Q000502:physiology*
chemical_list: D016232:Endothelins; D009599:Nitroprusside; D010656:Phenylephrine