title: Central cardiovascular effects of kappa agonists dynorphin-(1-13) and ethylketocyclazocine in the anaesthetized rat.
abstract: Opiate kappa agonists were administered into the cisterna magna of normotensive urethane-anaesthetized artificially ventilated rats: ethylketocyclazocine (78.7 nM) (EKC) and dynorphin-(1-13) (62.3 nM) produced significant and long-lasting decreases in both blood pressure and heart rate. High doses of naloxone (1 mg/kg i.v.) were required to partially antagonize these effects. The central cardiovascular effects of EKC and dynorphin-(1-13) were compared to those of fentanyl (3 nM), [D-Ala2,Met5]enkephalinamide (17 nM) and beta-endorphin (2.9 nM) which induced increases in blood pressure and heart rate. These results suggest that opposite central cardiovascular effects could be induced by activation of various opiate receptors.
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D003496:Cyclazocine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004399:Dynorphins; D004723:Endorphins / Q000494:pharmacology*; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives / Q000494:pharmacology; D016314:Ethylketocyclazocine; D005283:Fentanyl / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects*; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects*; D017473:Receptors, Opioid, kappa; D014630:Vagus Nerve / Q000502:physiology; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D010446:Peptide Fragments; D011957:Receptors, Opioid; D017473:Receptors, Opioid, kappa; D009270:Naloxone; D004744:Enkephalin, Methionine; D016314:Ethylketocyclazocine; D001615:beta-Endorphin; C022118:enkephalinamide-Met, Ala(2)-; C026843:dynorphin (1-13); D004399:Dynorphins; D003496:Cyclazocine; D005283:Fentanyl