title: Estrogen and progesterone effects on transcapillary fluid dynamics.
abstract: The purpose of this study was to determine estrogen (E(2)) and progesterone (P(4)) effects on atrial natriuretic peptide (ANP) control of plasma volume (PV) and transcapillary fluid dynamics. To this end, we suppressed reproductive function in 12 women (age 21-35 yr) using a gonadotropin releasing-hormone (GnRH) analog (leuprolide acetate) for 5 wk. During the 5th week, the women either received 4 days of E(2) administration (17beta-estradiol, transdermal patch, 0.1 mg/day) or 4 days of E(2) with P(4) administration (vaginal gel, 90 mg P(4) twice per day). At the end of the 4th and 5th week of GnRH analog and hormone administration, we determined PV (Evans blue dye) and changes in PV and forearm capillary filtration coefficient (CFC) during a 120-min infusion of ANP (5 ng x kg body wt(-1) x min(-1)). Preinfusion PV was estimated from Evans blue dye measurement taken over the last 30 min of infusion based on changes in hematocrit. E(2) treatment did not affect preinfusion PV relative to GnRH analog alone (45.3 +/- 3.1 vs. 45.4 +/- 3.1 ml/kg). During ANP infusion CFC was greater during E(2) treatment compared with GnRH analog alone (6.5 +/- 1.4 vs. 4.9 +/- 1.4 microl. 100 g(-1) x min(-1) mmHg(-1), P < 0.05). The %PV loss during ANP infusion was similar for E(2) and GnRH analog-alone treatments (-0.8 +/- 0.2 and -1.0 +/- 0.2 ml/kg, respectively), indicating the change in CFC had little systemic effect on ANP-related changes in PV. Estimated baseline PV was reduced by E(2)-P(4) treatment. During ANP infusion CFC was approximately 30% lower during E(2)-P(4) (6.0 +/- 0.5 vs. 4.3 +/- 4.3 microl. 100 g(-1) x min(-1) mm Hg(-1), P < 0.05), and the PV loss during ANP infusion was attenuated (-0.9 +/- 0.2 and -0.2 +/- 0.2 ml/kg for GnRH analog-alone and E(2)-P(4) treatments, respectively). Thus the E(2)-P(4) treatment lowered CFC and reduced PV loss during ANP infusion.
authors.affiliation: The John B. Pierce Laboratory and Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut 06519, USA. nstach@jbpierce.org
authors.forename: N S
authors.initials: NS
authors.lastname: Stachenfeld
authors.forename: D L
authors.initials: DL
authors.lastname: Keefe
authors.forename: S F
authors.initials: SF
authors.lastname: Palter
mesh_terms: D000328:Adult; D009320:Atrial Natriuretic Factor / Q000008:administration & dosage / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D001810:Blood Volume / Q000187:drug effects / Q000502:physiology; D002196:Capillaries / Q000187:drug effects* / Q000502:physiology*; D002199:Capillary Permeability / Q000187:drug effects*; D002302:Cardiac Output / Q000187:drug effects; D004333:Drug Administration Routes; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D005300:Fertility Agents, Female / Q000494:pharmacology; D005542:Forearm / Q000098:blood supply; D007987:Gonadotropin-Releasing Hormone / Q000009:adverse effects / Q000031:analogs & derivatives / Q000494:pharmacology; D006400:Hematocrit; D019584:Hot Flashes / Q000209:etiology; D006801:Humans; D007262:Infusions, Intravenous; D016729:Leuprolide / Q000009:adverse effects / Q000494:pharmacology; D011374:Progesterone / Q000494:pharmacology*; D013318:Stroke Volume / Q000187:drug effects; D014680:Veins / Q000502:physiology
chemical_list: D004967:Estrogens; D005300:Fertility Agents, Female; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D004958:Estradiol; D009320:Atrial Natriuretic Factor; D016729:Leuprolide