title: Effects of vitamin D3 derivative--calcitriol on pharmacological reactivity of aortic rings in a rodent PCOS model.
abstract: BACKGROUND
  The aim of this study was to examine the effects of the hyperandrogenic state in dihydrotestosterone (DHT)-induced polycystic ovary syndrome (PCOS), the vascular responses to different vasoactive agents, and the modulatory role of vitamin D3.
  
  
  METHODS
  APCOS model was induced by DHT application in 20 female Wistar rats. Ten of the DHT treated rats simultaneously received calcitriol treatment. After 10 weeks, myographs were used to test the reactivity of isolated thoracic aortic rings to norepinephrine and acetylcholine. Thereafter, the vascular rings were incubated with the NO-synthase blocker (nitro-L-arginine methyl ester) or the cyclooxygenase inhibitor (indomethacin) for 20 min, and the effects of norepinephrine and acetylcholine were re-evaluated.
  
  
  RESULTS
  Norepinephrine-induced vasoconstriction was enhanced after DHT treatment, but this effect was attenuated by calcitriol administration. Vasorelaxation of DHT-treated thoracic aortic rings was impaired, but this could be partly reversed by calcitriol application. Impaired NO-dependent vasorelaxation in DHT-treated animals was mostly reversed by concomitant calcitriol administration, but this effect was diminished by prostanoid-dependent vasoconstriction.
  
  
  CONCLUSIONS
  These studies show that the enhanced sensitivity to vasoconstrictors and impaired NO-dependent vasorelaxation in hyperandrogenic PCOS rats could be partially reversed by calcitriol treatment.
authors.affiliation: Department of Cardiology, Bajcsy Zs Hospital, Maglodi St 89-91, H-1106 Budapest, Hungary.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Masszi
authors.forename: Agnes
authors.initials: A
authors.lastname: Novak
authors.forename: Robert
authors.initials: R
authors.lastname: Tarszabo
authors.forename: Eszter Maria
authors.initials: EM
authors.lastname: Horvath
authors.forename: Anna
authors.initials: A
authors.lastname: Buday
authors.forename: Eva
authors.initials: E
authors.lastname: Ruisanchez
authors.forename: Anna-Maria
authors.initials: AM
authors.lastname: Tokes
authors.forename: Levente
authors.initials: L
authors.lastname: Sara
authors.forename: Rita
authors.initials: R
authors.lastname: Benko
authors.forename: Gyorgy L
authors.initials: GL
authors.lastname: Nadasy
authors.forename: Csaba
authors.initials: C
authors.lastname: Revesz
authors.forename: Peter
authors.initials: P
authors.lastname: Hamar
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Benyó
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Varbiro
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects* / Q000378:metabolism; D002117:Calcitriol / Q000494:pharmacology*; D013196:Dihydrotestosterone / Q000633:toxicity; D004195:Disease Models, Animal; D005260:Female; D007213:Indomethacin; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D009638:Norepinephrine / Q000494:pharmacology; D011085:Polycystic Ovary Syndrome / Q000188:drug therapy* / Q000503:physiopathology; D051381:Rats; D017208:Rats, Wistar; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
chemical_list: D013196:Dihydrotestosterone; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D002117:Calcitriol; D000109:Acetylcholine; D019331:NG-Nitroarginine Methyl Ester; D009638:Norepinephrine; D007213:Indomethacin