Functional evidence for oxygen-sensitive voltage-gated potassium channels in human placental vasculature.
Hypoxic fetoplacental vasoconstriction (HFPV), involving voltage-gated potassium (K(V)) channels, has been suggested in human placenta; the identity of these channels remains unclear. Using wire myography, chorionic plate blood vessels were exposed to isoform-specific K(V) channel blockers. Dose-response curves (thromboxane mimetic U46619; 0.1-2000 nM) pre- and post-addition of K(V) channel modulator were analysed. Arterial U46619-induced contraction increased with margatoxin and stromatoxin-1, whilst only correolide increased U46619-induced contraction in veins (P < 0.05 two-way ANOVA). Basal tone was unaffected in arteries or veins. These data implicate K(V)1.2 and/or K(V)2.1 and K(V)1.5 in the control of agonist-induced contraction of human placental arteries and veins respectively.
Kiernan
M F
MF
Maternal and Fetal Health Research Centre, School of Biomedicine, The University of Manchester, 5th Floor (Research), St. Mary's Hospital, Manchester, UK.
Barrie
A
A
Szkolar
J
J
Mills
T A
TA
Wareing
M
M
D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid / Q000494:pharmacology; D000704:Analysis of Variance; D001158:Arteries / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D010920:Placenta / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D012604:Scorpion Venoms / Q000494:pharmacology; D051637:Shaker Superfamily of Potassium Channels / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014315:Triterpenes / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects; D014680:Veins / Q000187:drug effects / Q000378:metabolism
D012604:Scorpion Venoms; D051637:Shaker Superfamily of Potassium Channels; D014315:Triterpenes; C118657:correolide; C087603:agitoxin 2; C077910:margatoxin; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid