title: Studies investigating the possible involvement of adenosine in the antisecretory action of morphine.
abstract: 1. Fluid secretion was induced in the jejunum of anesthetised rats using vasoactive intestinal peptide. 2. The adenosine antagonist, DPCPX (0.1 mg/kg), suppressed the antisecretory action of morphine (10 mg/kg), but naloxone (80 micrograms/kg) did not inhibit the antisecretory response of the adenosine agonist, NECA (40 micrograms/kg), at a dose previously shown to antagonize the antisecretory response of morphine. 3. NECA (40 (micrograms/kg) reversed secretion in pithed and reserpine-pretreated (5 mg/kg subcutaneously) rats. 4. It is proposed that adenosine acts as a mediator of the morphine antisecretory effect at a site distal to the noradrenergic neurons involved in the action of morphine.
authors.affiliation: Victorian College of Pharmacy, Monash University, Department of Pharmaceutical Biology and Pharmacology, Parkville Victoria, Australia.
authors.forename: D L
authors.initials: DL
authors.lastname: Hancock
authors.forename: I M
authors.initials: IM
authors.lastname: Coupar
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000494:pharmacology; D019830:Adenosine-5'-(N-ethylcarboxamide); D000818:Animals; D003655:Decerebrate State; D005260:Female; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000378:metabolism; D007583:Jejunum / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D009638:Norepinephrine / Q000378:metabolism; D058906:Purinergic P1 Receptor Agonists; D051381:Rats; D017208:Rats, Wistar; D012110:Reserpine / Q000494:pharmacology; D013565:Sympatholytics / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology; D014970:Xanthines / Q000494:pharmacology
chemical_list: D009292:Narcotic Antagonists; D058906:Purinergic P1 Receptor Agonists; D013565:Sympatholytics; D014970:Xanthines; D019830:Adenosine-5'-(N-ethylcarboxamide); D009270:Naloxone; D014660:Vasoactive Intestinal Peptide; D009020:Morphine; D012110:Reserpine; C051360:1,3-dipropyl-8-cyclopentylxanthine; D000241:Adenosine; D009638:Norepinephrine