Izvorni znanstveni članak
https://doi.org/10.3325/cmj.2015.56.114
ATP-sensitive potassium channels modulate in vitro tocolytic effects of β2- adrenergic receptor agonists on uterine muscle rings in rats in early but not in late pregnancy
Norbert Lovasz
; Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
Andrea Koncz
; Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
Dora Domokos
; Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
Robert Gaspar
; Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
György Falkay
; Department of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
Sažetak
Aim To investigate whether ATP-sensitive potassium (KATP)
channels modulate the tocolytic effect of β2-adrenergic
receptor (β2-AR) agonists (ritodrine and salmeterol) in early-
pregnant (day 6) and late-pregnant (day 22) rat uterus
in vitro, in order to examine the relation between the KATP
channel sulphonylurea-binding regulatory subunit (SUR)
expression and pharmacological reactivity of β2-AR agonists.
Methods The tocolytic effects of ritodrine and salmeterol
(10-10-10-5 M) on spontaneous rhythmic contractions were
investigated cumulatively, alone, or in the presence of the
KATP channel blocker glibenclamide (10-6 M) and the KATP
channel opener pinacidil (10-9-10-7 M) after 5-min preincubation.
Results β2-AR agonist induced myometrial relaxation was
inhibited by glibenclamide and enhanced by pinacidil on
day 6, when SUR1 expression levels were high. Neither
glibenclamide nor pinacidil mediated tocolytic effect was
measured on day 22.
Conclusion Low expression of the KATP channels at the
end of gestation may facilitate enhanced excitability and
contractility in the rat myometrium. The combination of a
betamimetic and a KATP channel opener will therefore not
be of therapeutic relevance in the treatment of preterm
delivery.
Ključne riječi
Hrčak ID:
139302
URI
Datum izdavanja:
15.4.2015.
Posjeta: 913 *