title: Ethnic differences in cyclic AMP accumulation: effect on alpha 2, beta 2, and prostanoid receptor responses.
abstract: Platelet alpha 2- and lymphocyte beta 2-adrenergic receptor density and responsiveness and platelet responses to prostaglandin E2 (PGE2) were measured in black subjects and white subjects. Mean (+/- SEM) alpha-receptor density was greater in white subjects (248 +/- 29 versus 392 +/- 31 fmol/mg protein; p less than 0.005), whereas beta-receptor densities were similar (black subjects, 19.2 +/- 2.2 fmol/mg protein; white subjects, 15.2 +/- 1.4 fmol/mg protein). Basal platelet cyclic AMP levels (black subjects, 7.8 +/- 1.1 pmol/mg protein; white subjects, 14.5 +/- 2.4 pmol/mg protein; p less than 0.05) and PGE2-induced increases in platelet cyclic AMP levels were higher in white subjects (black subjects, 47.1 +/- 3.3 pmol/mg protein; white subjects, 65.5 +/- 3.4 pmol/mg protein; p less than 0.001). Basal lymphocyte cyclic AMP levels (black subjects, 1.2 +/- 0.3 pmol/10(6) cells; white subjects, 2.8 +/- 0.6 pmol/10(6) cells; p less than 0.05) and mean isoproterenol-induced cyclic AMP increases were also higher in white subjects (black subjects, 6.2 +/- 0.6 pmol/10(6) cells; white subjects, 8.5 +/- 0.8 pmol/10(6) cells; p less than 0.05). Responses to isoproterenol as fold stimulation of basal were not significantly higher in black subjects (8.51 +/- 0.97 versus 6.16 +/- 0.86 fold-stimulation of basal). Platelet responses to PGE2 as fold stimulation of basal (black subjects, 7.9% +/- 0.7%; white subjects, 8% +/- 1.3%) and alpha 2-receptor-mediated inhibition of PGE2 responses by UK-14304 (black subjects, 38.2% +/- 1.7%; white subjects, 40.6% +/- 2.3%) were also similar in the two groups.
authors.affiliation: Department of Clinical Pharmacology, Royal College of Surgeons, Dublin, Ireland.
authors.forename: M
authors.initials: M
authors.lastname: Stein
authors.forename: K
authors.initials: K
authors.lastname: O'Malley
authors.forename: S
authors.initials: S
authors.lastname: Kilfeather
mesh_terms: D000328:Adult; D001481:Basal Metabolism; D044383:Black People; D001792:Blood Platelets / Q000378:metabolism; D000068438:Brimonidine Tartrate; D000242:Cyclic AMP / Q000378:metabolism* / Q000502:physiology; D015232:Dinoprostone / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D011810:Quinoxalines / Q000494:pharmacology; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D013268:Stimulation, Chemical; D044465:White People
chemical_list: D011810:Quinoxalines; D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D000068438:Brimonidine Tartrate; D000242:Cyclic AMP; D015232:Dinoprostone; D007545:Isoproterenol