title: Inhibitory effects of adrenaline on the release of noradrenaline from sympathetic nerves in human dental pulp.
abstract: The effects of adrenaline on the release of noradrenaline from sympathetic nerves in human dental pulp in vitro were examined. Sympathetic nerves were stimulated at 5 Hz for 100 sec following incubation of pulp with [3H]noradrenaline (0.6 micromol/l). In the presence of desipramine (DMI, 0.3 micromol/l), adrenaline (0.1 and 1.0 micromol/l) inhibited the release of [3H]noradrenaline, an effect which was inhibited by the alpha2-adrenoceptor antagonist rauwolscine (0.1 micromol/l) and by the alpha2-adrenoceptor agonist UK 14,304 (0.1 micromol/l). The release of [3H]noradrenaline was unaffected by adrenaline (0.001 and 0.01 micromol/l) in the presence of DMI and DMI plus rauwolscine. Although presynaptic inhibitory alpha2- and facilitatory beta-adrenoceptors are present on sympathetic nerves in human dental pulp, these results imply that adrenaline activates only the inhibitory alpha2-receptors.
authors.affiliation: Department of Dentistry, The University of Adelaide, South Australia, Australia. dparker@dentistry.adilaide.edu.au
authors.forename: D A
authors.initials: DA
authors.lastname: Parker
authors.forename: E
authors.initials: E
authors.lastname: Hennian
authors.forename: V
authors.initials: V
authors.lastname: Marino
authors.forename: I S
authors.initials: IS
authors.lastname: de la Lande
mesh_terms: D000293:Adolescent; D000322:Adrenergic Agonists / Q000494:pharmacology*; D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology; D000316:Adrenergic alpha-Agonists / Q000378:metabolism* / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000328:Adult; D000068438:Brimonidine Tartrate; D046508:Culture Techniques; D003782:Dental Pulp / Q000294:innervation*; D003891:Desipramine / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology*; D006801:Humans; D009638:Norepinephrine / Q000378:metabolism*; D011810:Quinoxalines / Q000494:pharmacology; D019275:Radiopharmaceuticals; D017661:Receptors, Presynaptic / Q000037:antagonists & inhibitors / Q000187:drug effects; D013564:Sympathetic Nervous System / Q000187:drug effects* / Q000378:metabolism; D014316:Tritium; D015016:Yohimbine / Q000494:pharmacology
chemical_list: D000322:Adrenergic Agonists; D018759:Adrenergic Uptake Inhibitors; D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D011810:Quinoxalines; D019275:Radiopharmaceuticals; D017661:Receptors, Presynaptic; D014316:Tritium; D015016:Yohimbine; D000068438:Brimonidine Tartrate; D003891:Desipramine; D009638:Norepinephrine; D004837:Epinephrine