title: The effects of meperidine in the pulmonary vascular bed of the cat.
abstract: OBJECTIVE
  The purpose of this study was to test the hypothesis that meperidine induces a dilator response in the feline pulmonary vascular bed, and to identify receptors involved in the mediation or modulation of these effects.
  
  
  METHODS
  Prospective vehicle controlled study.
  
  
  METHODS
  University research laboratory.
  
  
  METHODS
  Intact chest preparation; adult mongrel cats.
  
  
  METHODS
  In separate experiments, the effects of diphenydramine (histamine H(1)-receptor antagonist), glibenclamide (adenosine triphosphate-sensitive K+ channel blocker), L-N(5)-(1-Iminoethyl) ornithine hydrochloride (L-NIO) (nitric oxide synthase inhibitor), naloxone (opioid receptor antagonist), and nimesulide (selective cyclooxygenase-2 inhibitor) were investigated on pulmonary arterial responses to meperidine and other agonists in the feline lung bed.
  
  
  RESULTS
  The systemic pressure and lobar arterial perfusion pressure were continuously monitored, electronically averaged, and permanently recorded. Under elevated tone conditions in the isolated left lower lobe vascular bed of the cat, meperidine induced a dose-dependent vasodilator response that was not significantly altered after administration of glibenclamide, L-NIO, and nimesulide. Responses to meperidine were significantly attenuated after the administration of diphenydramine and naloxone.
  
  
  CONCLUSIONS
  The results suggest that meperidine has potent vasodilator activity in the feline pulmonary vascular bed, and these responses are mediated or modulated, in part, by opioid and histamine receptor-sensitive pathways.
authors.affiliation: Department of Anesthesiology, Louisiana State University Health Sciences Center, New Orleans, LA, USA. akaye@lsuhsc.edu <akaye@lsuhsc.edu>
authors.forename: Alan D
authors.initials: AD
authors.lastname: Kaye
authors.forename: Jason M
authors.initials: JM
authors.lastname: Hoover
authors.forename: Syed R
authors.initials: SR
authors.lastname: Baber
authors.forename: Ikhlass N
authors.initials: IN
authors.lastname: Ibrahim
authors.forename: James
authors.initials: J
authors.lastname: Phelps
authors.forename: Aaron
authors.initials: A
authors.lastname: Fields
authors.forename: Amir
authors.initials: A
authors.lastname: Baluch
authors.forename: Shane
authors.initials: S
authors.lastname: Huffman
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D002415:Cats; D005260:Female; D005500:Follow-Up Studies; D006976:Hypertension, Pulmonary / Q000503:physiopathology / Q000517:prevention & control / Q000662:veterinary; D008297:Male; D008614:Meperidine / Q000494:pharmacology*; D011379:Prognosis; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000187:drug effects* / Q000502:physiology; D011667:Pulmonary Veins / Q000187:drug effects* / Q000502:physiology; D011669:Pulmonary Wedge Pressure / Q000187:drug effects / Q000502:physiology*; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*
chemical_list: D000701:Analgesics, Opioid; D008614:Meperidine