title: Effects of yohimbine and desipramine on adrenal catecholamine release in response to splanchnic nerve stimulation in anesthetized dogs.
abstract: The effects of yohimbine and desipramine on adrenal catecholamine (CA) release in response to splanchnic nerve stimulation (SNS) were examined in anesthetized dogs. SNS and 3 Hz produced frequency-dependent increases in epinephrine (EPI) and norepinephrine (NE) output determined from adrenal venous blood. Yohimbine (30 and 100 micrograms/kg, i.v.), a selective alpha 2-adrenoceptor antagonist, enhanced the SNS-induced increases in both EPI and NE output. Desipramine (100 and 300 micrograms/kg, i.v.), an amine pump inhibitor, enhanced the SNS-induced increases in NE output, whereas no enhancement of EPI output was produced. After desipramine treatment, yohimbine further enhanced the SNS-induced increases in EPI and NE output. After yohimbine treatment, desipramine further enhanced the SNS-induced increase in NE output. These results suggest that the release of adrenal CA in response to SNS is inhibited by alpha 2-adrenoceptors, and that released NE, rather than EPI, is predominantly taken up into the dog adrenal medullary cells.
authors.affiliation: Department of Pharmacology, Pharmaceutical Institute, Tohoku University, Sendai, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Koganei
authors.forename: A
authors.initials: A
authors.lastname: Takeuchi
authors.forename: T
authors.initials: T
authors.lastname: Kimura
authors.forename: S
authors.initials: S
authors.lastname: Satoh
mesh_terms: D000311:Adrenal Glands / Q000187:drug effects* / Q000378:metabolism; D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000758:Anesthesia; D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D003891:Desipramine / Q000494:pharmacology*; D004285:Dogs; D004558:Electric Stimulation; D005260:Female; D008297:Male; D013153:Splanchnic Nerves / Q000502:physiology*; D014439:Tyramine / Q000494:pharmacology; D015016:Yohimbine / Q000494:pharmacology*
chemical_list: D018759:Adrenergic Uptake Inhibitors; D000317:Adrenergic alpha-Antagonists; D002395:Catecholamines; D015016:Yohimbine; D003891:Desipramine; D014439:Tyramine