Calcium-activated potassium channels are important in a variety of smooth muscles, contributing to excitability and contractility. In the myometrium previous work has focussed on the large conductance channels (BK), and the role of small conductance channels (SK) has received scant attention, despite the finding that over-expression of an SK channel isoform (SK3) results in uterine dysfunction and delayed parturition. This study therefore characterises the expression of the three SK channel isoforms (SK1-3) in rat myometrium throughout pregnancy and investigates their effect on cytosolic [Ca] and force and compares this with that of BK channels. Consistent expression of all SK isoform transcripts and clear immunostaining of SK1-3 was found. Inhibition of SK1-3 channels (apamin, scyllatoxin) significantly inhibited outward current, caused membrane depolarisation and elicited action potentials in previously quiescent cells. Apamin or scyllatoxin increased the amplitude of [Ca] and force in spontaneously contracting myometrial strips throughout gestation. The functional effect of SK inhibition was larger than that of BK channel inhibition. Thus we show for the first time that SK1-3 channels are expressed and translated throughout pregnancy and contribute to outward current, regulate membrane potential and hence Ca signals in pregnant rat myometrium. They contribute more to quiescence that BK channels.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ceca.2009.11.004 | DOI Listing |
Sci Rep
January 2025
Science and Technology Innovation Center, Shandong Provincial Key Medical and Health Laboratory of Blood Ecology and Biointelligence, Jinan Key Laboratory of Medical Cell Bioengineering, Cardio- cerebrovascular Disease Hospital of Jinan, The Fourth People's Hospital of Jinan, The Teaching Hospital of Shandong Second Medical University, 50 Shifan Road, Tianqiao District, Jinan, 250031, Shandong, China.
Previous cesarean scar defect (PCSD), also acknowledged as the myometrium of uterus defects, which commonly results in myometrial discontinuity between the uterine and cervical cavity. Current literatures have indicated the efficacy of MSCs and MSC-derived exosomes (MSC-Exos) for diverse refractory disease administration, yet the feasibility of MSC-Exos for PCSD treatment is largely obscure. In this study, we took advantage of the in vivo myofibrotic model for mimicking the typical manifestation of PCSD and the assessment of fertility.
View Article and Find Full Text PDFReprod Toxicol
January 2025
Molecular Toxicology Laboratory, Department of Medical Elementology and Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India. Electronic address:
There is a rising incidence of polycystic ovary syndrome (PCOS) cases worldwide in women of reproductive age due to environmental factors. We evaluated the effect of an environmental estrogen, bisphenol A (BPA) for its reprotoxicity regarding the induction of PCOS in rats and also assessed its hormonal and metabolic implications. There was 66.
View Article and Find Full Text PDFJ Anat
January 2025
Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
Histochem Cell Biol
November 2024
Department of Histology and Embryology, Istanbul University-Cerrahpasa, Istanbul, Turkey.
Telocytes (TCs) are characterized by a small oval-shaped cell body with long prolongations that are called telopods (Tps). PDGFR-β and c-kit markers may assist for the immunohistochemical identification of TCs; however, by these means they cannot be identified with absolute specificity. Transmission electron microscopy (TEM) is considered as a gold standard method for TCs observation.
View Article and Find Full Text PDFStem Cell Res Ther
July 2024
Center for Reproductive Medicine and Obstetrics and Gynecology, Nanjing Drum Tower Hospital, Clinical College of Nanjing University of Chinese Medicine, Nanjing, 210008, China.
Background: Intrauterine adhesions (IUAs) jeopardise uterine function in women, which is a great challenge in the clinic. Previous studies have shown that endometrial perivascular cells (En-PSCs) can improve the healing of scarred uteri and that hydroxysafflor yellow A (HSYA) promotes angiogenesis. The purpose of this study was to observe whether the combination of En-PSCs with HSYA could improve the blood supply and fertility in the rat uterus after full-thickness injury.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!