Show simple item record

dc.contributor.authorFerreira, J.J.
dc.contributor.authorButler, A.
dc.contributor.authorStewart, R.
dc.date.accessioned2019-09-13T16:42:00Z
dc.date.available2019-09-13T16:42:00Z
dc.date.issued2019
dc.identifier.urihttps://www.scopus.com/inward/record.uri?eid=2-s2.0-85056821056&doi=10.1113%2fJP276806&partnerID=40&md5=d7a5338fb36cb8709ba4deac5c65b502
dc.identifier.urihttp://hdl.handle.net/10713/10707
dc.description.abstractKey points: At the end of pregnancy, the uterus transitions from a quiescent state to a highly contractile state. This transition requires that the uterine (myometrial) smooth muscle cells increase their excitability, although how this occurs is not fully understood. We identified SLO2.1, a potassium channel previously unknown in uterine smooth muscle, as a potential significant contributor to the electrical excitability of myometrial smooth muscle cells. We found that activity of the SLO2.1 channel is negatively regulated by oxytocin via G?q-protein-coupled receptor activation of protein kinase C. This results in depolarization of the uterine smooth muscle cells and calcium entry, which may contribute to uterine contraction. These findings provide novel insights into a previously unknown mechanism by which oxytocin may act to modulate myometrial smooth muscle cell excitability. Our findings also reveal a new potential pharmacological target for modulating uterine excitability. Abstract: During pregnancy, the uterus transitions from a quiescent state to a more excitable contractile state. This is considered to be at least partly a result of changes in the myometrial smooth muscle cell (MSMC) resting membrane potential. However, the ion channels controlling the myometrial resting membrane potential and the mechanism of transition to a more excitable state have not been fully clarified. In the present study, we show that the sodium-activated, high-conductance, potassium leak channel, SLO2.1, is expressed and active at the resting membrane potential in MSMCs. Additionally, we report that SLO2.1 is inhibited by oxytocin binding to the oxytocin receptor. Inhibition of SLO2.1 leads to membrane depolarization and activation of voltage-dependent calcium channels, resulting in calcium influx. The results of the present study reveal that oxytocin may modulate MSMC electrical activity by inhibiting SLO2.1 potassium channels. Copyright 2018 The Authors.en_US
dc.description.sponsorshipThis work was supported by Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) R01 HD088097 to CMS and SKE as well as (NIGMS and NIMH) R01 GM114694 and R21MH107955 to LS, respectively.en_US
dc.description.urihttps://doi.org/10.1113/JP276806en_US
dc.language.isoen-USen_US
dc.publisherBlackwell Publishing Ltden_US
dc.relation.ispartofJournal of Physiology
dc.subjectMyometriumen_US
dc.subjectOxytocinen_US
dc.subjectSLO2.1 Potassium channelsen_US
dc.subjectSmooth muscleen_US
dc.titleOxytocin can regulate myometrial smooth muscle excitability by inhibiting the Na + -activated K + channel, Slo2.1en_US
dc.typeArticleen_US
dc.identifier.doi10.1113/JP276806
dc.identifier.pmid30334255


This item appears in the following Collection(s)

Show simple item record