title: Prostaglandins do not mediate the inhibitory effects of angiotensins II and III on autonomic neurotransmission in the rabbit vas deferens.
abstract: The role of prostaglandins in mediating angiotensin effects on autonomic neurotransmission was assessed. This was accomplished by examining the angiotensin-induced production of prostaglandins (PGE) and suppression of non-adrenergic (purinergic) neurotransmission in the presence and absence of cyclo-oxygenase inhibitors. The vas deferens of the rabbit was utilized for these studies because this preparation has a predominant non-adrenergic neurogenic component. Both angiotensins II and III enhanced PGE production and reduced non-adrenergic neurogenic contractions in a concentration-dependent manner from 1 to 1000 nM. Furthermore, indomethacin (2.8 microM) and eicosatetraynoic acid (10 microM) eliminated the inhibitory effect of the angiotensins on non-adrenergic neurotransmission. However, acetylsalicylic acid (10 microM) prevented the production of PGE in response to the angiotensins but failed to alter the suppression of non-adrenergic neurotransmission. The latter data are inconsistent with the hypothesis that PG's mediate angiotensin-induced depression of non-adrenergic neurotransmission. The mechanism by which indomethacin and eicosatetraynoic acid prevent angiotensin effects on non-adrenergic neurotransmission was not elucidated but previous reports suggest that these agents may act as angiotensin receptor antagonists. All of the cyclo-oxygenase inhibitors examined tended to potentiate angiotensin effects on adrenergic neurotransmission.
authors.affiliation: Department of Pharmacology, University of Minnesota-Duluth, Medical School, 55812.
authors.forename: G J
authors.initials: GJ
authors.lastname: Trachte
mesh_terms: D015117:5,8,11,14-Eicosatetraynoic Acid / Q000494:pharmacology; D000804:Angiotensin II / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000805:Angiotensin III / Q000494:pharmacology*; D000818:Animals; D001241:Aspirin / Q000494:pharmacology; D001341:Autonomic Nervous System / Q000187:drug effects*; D004357:Drug Synergism; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D011458:Prostaglandins E / Q000494:pharmacology*; D011817:Rabbits; D009435:Synaptic Transmission / Q000187:drug effects*; D014649:Vas Deferens / Q000294:innervation*
chemical_list: D011458:Prostaglandins E; D000804:Angiotensin II; D015117:5,8,11,14-Eicosatetraynoic Acid; D000805:Angiotensin III; D001241:Aspirin; D007213:Indomethacin