title: Additive inhibitory effects of progesterone and sodium nitroprusside on uterine contractility during pregnancy.
abstract: Progesterone (P4) and nitric oxide (NO) suppress uterine contractility (CTX). This study compares the effects of P4 to sodium nitroprusside (SNP, an NO donor) and their combination on human CTX of term/preterm and labor/nonlabor tissues. Uterine tissues (n = 128) from women (n = 28) undergoing Cesarean were suspended in organ baths. Tissues (n ≥ 6/group) were treated with vehicle, P4, SNP, or combinations. A subset of tissues (n ≥ 2/group) from term/preterm ± labor and nonpregnant patients was analyzed with P4 alone. Analysis of variance (ANOVA) was used for statistical differences (P < .05). The combination of P4 with SNP significantly suppresses CTX (% inhibition of -127.1 ± 14.5) to the levels lower than with either P4 (-20.1 ± 8.6) or SNP alone (-72.0 ± 11.2). Suppression of P4 is similar in term, preterm, and nonpregnant tissues, with increased sensitivity in laboring tissues. This indicates that P4 or SNP alone may be used for preterm labor and their combination may be more successful.
authors.affiliation: Obstetrics and Gynecology Department, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA.
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Orth
authors.forename: Shao-Qing
authors.initials: SQ
authors.lastname: Shi
authors.forename: Kelli
authors.initials: K
authors.lastname: Williamson
authors.forename: Leili
authors.initials: L
authors.lastname: Shi
authors.forename: Linda
authors.initials: L
authors.lastname: Chambliss
authors.forename: Dean V
authors.initials: DV
authors.lastname: Coonrod
authors.forename: James
authors.initials: J
authors.lastname: Balducci
authors.forename: Robert E
authors.initials: RE
authors.lastname: Garfield
mesh_terms: D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007743:Labor, Obstetric / Q000187:drug effects*; D009215:Myometrium / Q000187:drug effects*; D020030:Nitric Oxide Donors / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology*; D011247:Pregnancy; D011374:Progesterone / Q000494:pharmacology*; D014590:Uterine Contraction / Q000187:drug effects*
chemical_list: D020030:Nitric Oxide Donors; D009599:Nitroprusside; D011374:Progesterone