title: Effect of acute transdermal estrogen administration on basal, mental stress and cold pressor-induced sympathetic responses in postmenopausal women.
abstract: Administration of estrogen has vascular effects through poorly defined mechanisms that may include sympathetic withdrawal. To define the effects of acute estrogen administration on sympathetic responses, nineteen healthy postmenopausal women (age 54+/-2 years) were studied after application of a placebo or estrogen patch for 36 hours, in random order. A p-value, adjusted for multiple comparisons, of <0.017 was used to determine statistical significance. Heart rate, blood pressure, and norepinephrine spillover were measured at rest, during mental stress (Stroop test), and during a cold pressor test. Estrogen did not attenuate basal or stimulated hemodynamic responses significantly. The increase in mean arterial pressure after the Stroop test (5.9+/-1.2mm/ Hg on placebo vs 6.1+/-1.6mm/Hg on estrogen, p=0.9) and after the cold pressor test (12.6+/-2.4mm/Hg on placebo vs 13.0+/-2.2 mm/Hg on estrogen, p=0.8) did not differ. Basal, mental stress and cold pressor-stimulated norepinephrine spillover were not significantly affected by short-term estrogen administration. Norepinephrine spillover tended to be higher after estrogen (1296.2+/-238 ng/min) than placebo (832.5+/-129 ng/min) (p=0.02) at baseline and after the Stroop test (1881.1+/-330 ng/min vs 1014.6+/-249 ng/min) (p=0.02). Acute transdermal estrogen administration did not attenuate norepinephrine spillover or sympathetically mediated hemodynamic responses.
authors.affiliation: Division of Clinical Pharmacology, 560 MRB 1, Vanderbilt University Medical School, Nashville, TN 37232-6602, USA.
authors.forename: Gbemiga G
authors.initials: GG
authors.lastname: Sofowora
authors.forename: Iqbal
authors.initials: I
authors.lastname: Singh
authors.forename: Huai B
authors.initials: HB
authors.lastname: He
authors.forename: Alastair J J
authors.initials: AJ
authors.lastname: Wood
authors.forename: C Michael
authors.initials: CM
authors.lastname: Stein
mesh_terms: D000279:Administration, Cutaneous; D001794:Blood Pressure / Q000187:drug effects*; D002395:Catecholamines / Q000097:blood; D003080:Cold Temperature / Q000009:adverse effects*; D004967:Estrogens / Q000008:administration & dosage* / Q000627:therapeutic use*; D005260:Female; D005542:Forearm / Q000098:blood supply; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D017698:Postmenopause / Q000502:physiology*; D011312:Pressure; D012039:Regional Blood Flow / Q000187:drug effects; D013315:Stress, Psychological / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000187:drug effects* / Q000502:physiology*
chemical_list: D002395:Catecholamines; D004967:Estrogens; D009638:Norepinephrine