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Dawson M, Flores D, Zou L, Anandasenthil S, Mahesh R, Zavala-Romero O, Arora R. Imaging the dynamics of murine uterine contractions in early pregnancy†. Biol Reprod 2024; 110:1175-1190. [PMID: 38713674 PMCID: PMC11180618 DOI: 10.1093/biolre/ioae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 04/03/2024] [Accepted: 05/02/2024] [Indexed: 05/09/2024] Open
Abstract
Uterine muscle contractility is essential for reproductive processes including sperm and embryo transport, and during the uterine cycle to remove menstrual effluent. Even still, uterine contractions have primarily been studied in the context of preterm labor. This is partly due to a lack of methods for studying the uterine muscle contractility in the intact organ. Here, we describe an imaging-based method to evaluate mouse uterine contractility of both the longitudinal and circular muscles in the cycling stages and in early pregnancy. By transforming the image-based data into three-dimensional spatiotemporal contractility maps, we calculate waveform characteristics of muscle contractions, including amplitude, frequency, wavelength, and velocity. We report that the native organ is highly contractile during the progesterone-dominant diestrus stage of the cycle when compared to the estrogen-dominant proestrus and estrus stages. We also observed that during the first phase of uterine embryo movement when clustered embryos move toward the middle of the uterine horn, contractions are dynamic and non-uniform between different segments of the uterine horn. In the second phase of embryo movement, contractions are more uniform and rhythmic throughout the uterine horn. Finally, in Lpar3-/- uteri, which display faster embryo movement, we observe global and regional increases in contractility. Our method provides a means to understand the wave characteristics of uterine smooth muscle in response to modulators and in genetic mutants. Better understanding uterine contractility in the early pregnancy stages is critical for the advancement of artificial reproductive technologies and a possibility of modulating embryo movement during clinical embryo transfers.
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Affiliation(s)
- Madeline Dawson
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, Michigan, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Diana Flores
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, Michigan, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Lisa Zou
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, Michigan, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Shivani Anandasenthil
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, Michigan, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Rohit Mahesh
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, Michigan, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan, USA
| | - Olmo Zavala-Romero
- Department of Scientific Computing, Florida State University, Tallahassee, Florida, USA
| | - Ripla Arora
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, East Lansing, Michigan, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan, USA
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Combs DJ, Moult EM, England SK, Cohen AE. Mapping uterine calcium dynamics during the ovulatory cycle in live mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.02.578395. [PMID: 38370720 PMCID: PMC10871303 DOI: 10.1101/2024.02.02.578395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Uterine contraction patterns vary during the ovulatory cycle and throughout pregnancy but prior measurements have produced limited and conflicting information on these patterns. We combined a virally delivered genetically encoded calcium reporter (GCaMP8m) and ultra-widefield imaging in live nonpregnant mice to characterize uterine calcium dynamics at organ scale throughout the estrous cycle. Prior to ovulation (proestrus and estrus) uterine excitations primarily initiated in a region near the oviduct, but after ovulation (metestrus and diestrus), excitations initiated at loci homogeneously distributed throughout the organ. The frequency of excitation events was lowest in proestrus and estrus, higher in metestrus and highest in diestrus. These results establish a platform for mapping uterine activity, and show that the question of whether there is an anatomically localized trigger for uterine excitations depends on the estrous cycle phase.
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Affiliation(s)
- David J. Combs
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School
- Department of Chemistry and Chemical Biology, Harvard University
| | - Eric M. Moult
- Department of Chemistry and Chemical Biology, Harvard University
| | - Sarah K. England
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University School of Medicine
| | - Adam E. Cohen
- Department of Chemistry and Chemical Biology, Harvard University
- Department of Physics, Harvard University
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Fischer DP, Griffiths AL, Lui S, Sabar UJ, Farrar D, O'Donovan PJ, Woodward DF, Marshall KM. Distribution and Function of Prostaglandin E 2 Receptors in Mouse Uterus: Translational Value for Human Reproduction. J Pharmacol Exp Ther 2020; 373:381-390. [PMID: 32205366 DOI: 10.1124/jpet.119.263509] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 03/10/2020] [Indexed: 12/19/2022] Open
Abstract
Prostaglandin (PG) E analogs are used clinically to ripen the cervix and induce labor. However, selective receptor agonists may have potential to improve induction response rates or manage unwanted uterine hypercontractility in conditions such as dysmenorrhea and preterm labor. To characterize their therapeutic value, PGE2 analogs were used to investigate the functional E-type prostanoid (EP) receptor population in isolated human uterus. Responsiveness in mouse tissues was also examined to validate its use as a preclinical model. Uterine samples were obtained from mice at dioestrus (n = 12), term gestation (n = 14), and labor (n = 12) and from the lower uterus of women undergoing hysterectomy (n = 12) or Caesarean section (n = 18). Vehicle and agonist effects were assessed using superfusion and immersion techniques. PGE2 evoked predominant excitatory responses in mouse and relaxation in human tissues. Selective EP4 agonists inhibited tissue activity in both nonpregnant species, while the EP2 mimetic CP533536 also attenuated uterine contractions throughout gestation. The uterotonic effects of the EP3/1 agonist sulprostone were more pronounced than the EP1 agonist ONO-D1-004, corresponding to abundant EP3 receptor expression in all samples. The contractile phenotype in mouse compared with human uteri may relate to regional differences as well as high expression of EP3 receptor transcripts. Similarities in nonpregnant and gestational tissues across species suggest that EP3 may represent a valuable translational drug target for preventing uterine hypercontractility by employing a selective antagonist. SIGNIFICANCE STATEMENT: This research validates the use of nonpregnant mice for preclinical drug discovery of uterine EP receptor targets. To determine the utility of novel drugs and delivery systems at term pregnancy and labor, pharmacological agents interacting with EP3 receptors have clear translational value.
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Affiliation(s)
- Deborah P Fischer
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.).
| | - Anna L Griffiths
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
| | - Sylvia Lui
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
| | - Uzmah J Sabar
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
| | - Diane Farrar
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
| | - Peter J O'Donovan
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
| | - David F Woodward
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
| | - Kay M Marshall
- Division of Pharmacy and Optometry, School of Health Sciences (D.P.F., K.M.M.) and Division of Developmental Biology and Medicine, School of Medical Sciences (S.L.), Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; School of Pharmacy, University of Bradford, Bradford, West Yorkshire, United Kingdom (A.L.G., U.J.S.); Bradford Institute for Health Research, Bradford Royal Infirmary, Duckworth Lane, Bradford, West Yorkshire, United Kingdom (D.F.); Obstetrics and Gynaecological Oncology, Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom (P.J.D.); Department of Bioengineering, Imperial College London, London, United Kingdom (D.F.W.); and JeniVision Inc., Irvine, California, USA (D.F.W.)
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4
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Bafor EE, Rowan EG, Edrada-Ebel R. Metabolomics-Coupled Functional Pharmacology of Chlorophyll Compounds Isolated From the Leaves of Ficus Exasperata Vahl (Moraceae) Provides Novel Pathways on Myometrial Activity. Reprod Sci 2017; 25:923-937. [DOI: 10.1177/1933719117732159] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Enitome E. Bafor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, United Kingdom
- Department of Pharmacology and Toxicology, University of Benin, Benin City, Nigeria
| | - Edward G. Rowan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, United Kingdom
| | - RuAngelie Edrada-Ebel
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, United Kingdom
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Pagano E, Orlando P, Finizio S, Rossi A, Buono L, Iannotti FA, Piscitelli F, Izzo AA, Di Marzo V, Borrelli F. Role of the endocannabinoid system in the control of mouse myometrium contractility during the menstrual cycle. Biochem Pharmacol 2016; 124:83-93. [PMID: 27899300 DOI: 10.1016/j.bcp.2016.11.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/25/2016] [Indexed: 10/20/2022]
Abstract
Cannabis and cannabinoids are known to affect female reproduction. However, the role of the endocannabinoid system in mouse uterine contractility in the dioestrus and oestrus phases has not been previously investigated. The present study aimed at filling this gap. Endocannabinoid (anandamide and 2-arachidonoylglycerol) levels were measured in mouse uterus at dioestrus and oestrus phases by liquid chromatography-mass spectrometry; quantitative reverse transcription-PCR and western blot were used to measured the expression of cannabinoid receptors and enzymes involved in the metabolism of endocannabinoids. Contractility was evaluated in vitro either on the spontaneous contractions or by stimulating the isolated uterus with exogenous spasmogens. The tissue concentrations of anandamide and 2-AG were reduced in the oestrus phase, compared to dioestrus. Uteri obtained in the dioestrus, but not oestrus, phase showed spontaneous phasic prostaglandin-mediated contractions that were reduced by ACEA (CB1 receptor agonist) and to a lower extent by JWH133 (CB2 receptor agonist). These inhibitory effects were counteracted by the corresponding selective antagonists. Neither ACEA nor JWH133 did affect the contractions induced by exogenous PGE2 in the uterus from the oestrus phase. The FAAH inhibitor JNJ1661010 and, to a lower extent, the MAGL inhibitor JZL184 also reduced spontaneous contractions. It is concluded that the endocannabinoid system undergoes to adaptive changes between the oestrus and dioestrus phases. CB1 and, to a lower extent, CB2 receptor activation results in selective inhibition of myometrial contractility, without un-specific relaxing effects on the smooth muscle. These results might be of interest for female marijuana smokers as well as for the design of novel tocolytic agents.
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Affiliation(s)
- Ester Pagano
- Department of Pharmacy, University of Naples Federico II, Naples, Italy; Endocannabinoid Research Group, National Research Council, Naples, Italy
| | - Pierangelo Orlando
- Endocannabinoid Research Group, National Research Council, Naples, Italy; Institute of Protein Biochemistry, National Research Council, Naples, Italy; Institute of Applied Sciences & Intelligent Systems, National Research Council, Pozzuoli, Naples, Italy
| | - Stefania Finizio
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Antonietta Rossi
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Lorena Buono
- Endocannabinoid Research Group, National Research Council, Naples, Italy; Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Naples, Italy
| | - Fabio Arturo Iannotti
- Endocannabinoid Research Group, National Research Council, Naples, Italy; Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Naples, Italy
| | - Fabiana Piscitelli
- Endocannabinoid Research Group, National Research Council, Naples, Italy; Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Naples, Italy
| | - Angelo A Izzo
- Department of Pharmacy, University of Naples Federico II, Naples, Italy; Endocannabinoid Research Group, National Research Council, Naples, Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, National Research Council, Naples, Italy; Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Naples, Italy
| | - Francesca Borrelli
- Department of Pharmacy, University of Naples Federico II, Naples, Italy; Endocannabinoid Research Group, National Research Council, Naples, Italy.
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6
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Dodds KN, Staikopoulos V, Beckett EAH. Uterine Contractility in the Nonpregnant Mouse: Changes During the Estrous Cycle and Effects of Chloride Channel Blockade. Biol Reprod 2015; 92:141. [PMID: 25926436 DOI: 10.1095/biolreprod.115.129809] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 04/22/2015] [Indexed: 11/01/2022] Open
Abstract
Mechanisms involved in the generation of spontaneous uterine contractions are not fully understood. Kit-expressing interstitial cells of Cajal are pacemakers of contractile rhythm in other visceral organs, and recent studies describe a role for Ca(2+)-activated Cl(-) currents as the initiating conductance in these cells. The existence and role of similar specialized pacemaker cells in the nonpregnant uterus remains undetermined. Spontaneous contractility patterns were characterized throughout the estrous cycle in isolated, nonpregnant mouse uteri using spatiotemporal mapping and tension recordings. During proestrus, estrus, and diestrus, contraction origin predominated in the oviduct end of the uterus, suggesting the existence of a dominant pacemaker site. Propagation speed of contractions during estrus and diestrus were significantly slower than in proestrus and metestrus. Five major patterns of activity were predominantly exhibited in particular stages: quiescent (diestrus), high-frequency phasic (proestrus), low-frequency phasic (estrus), multivariant (metestrus), and complex. Kit-immunopositive cells reminiscent of pacemaking ICCs were not consistently observed within the uterus. Niflumic acid (10 μM), anthracene-9-carboxylic acid (0.1-1 mM), and 5-nitro-2-(3-phenylpropylamino)benzoic acid (10 μM) each reduced the frequency of spontaneous contractions, suggesting involvement of Cl(-) channels in generating spontaneous uterine motor activity. It is unlikely that this conductance is generated by the Ca(2+)-activated Cl(-) channels, anoctamin-1 and CLCA4, as immunohistochemical labeling did not reveal protein expression within muscle or pacemaker cell networks. In summary, these results suggest that spontaneous uterine contractions may be generated by a Kit-negative pacemaker cell type or uterine myocytes, likely involving the activity of a yet-unidentified Cl(-) channel.
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Affiliation(s)
- Kelsi N Dodds
- Discipline of Physiology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Vasiliki Staikopoulos
- Discipline of Physiology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Elizabeth A H Beckett
- Discipline of Physiology, School of Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia
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Gravina FS, van Helden DF, Kerr KP, de Oliveira RB, Jobling P. Phasic contractions of the mouse vagina and cervix at different phases of the estrus cycle and during late pregnancy. PLoS One 2014; 9:e111307. [PMID: 25337931 PMCID: PMC4206458 DOI: 10.1371/journal.pone.0111307] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 09/30/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND/AIMS The pacemaker mechanisms activating phasic contractions of vaginal and cervical smooth muscle remain poorly understood. Here, we investigate properties of pacemaking in vaginal and cervical tissues by determining whether: 1) functional pacemaking is dependent on the phase of the estrus cycle or pregnancy; 2) pacemaking involves Ca2+ release from sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) -dependent intracellular Ca2+ stores; and 3) c-Kit and/or vimentin immunoreactive ICs have a role in pacemaking. METHODOLOGY/PRINCIPAL FINDINGS Vaginal and cervical contractions were measured in vitro, as was the distribution of c-Kit and vimentin positive interstitial cells (ICs). Cervical smooth muscle was spontaneously active in estrus and metestrus but quiescent during proestrus and diestrus. Vaginal smooth muscle was normally quiescent but exhibited phasic contractions in the presence of oxytocin or the K+ channel blocker tetraethylammonium (TEA) chloride. Spontaneous contractions in the cervix and TEA-induced phasic contractions in the vagina persisted in the presence of cyclopiazonic acid (CPA), a blocker of the SERCA that refills intracellular SR Ca2+ stores, but were inhibited in low Ca2+ solution or in the presence of nifedipine, an inhibitor of L-type Ca2+channels. ICs were found in small numbers in the mouse cervix but not in the vagina. CONCLUSIONS/SIGNIFICANCE Cervical smooth muscle strips taken from mice in estrus, metestrus or late pregnancy were generally spontaneously active. Vaginal smooth muscle strips were normally quiescent but could be induced to exhibit phasic contractions independent on phase of the estrus cycle or late pregnancy. Spontaneous cervical or TEA-induced vaginal phasic contractions were not mediated by ICs or intracellular Ca2+ stores. Given that vaginal smooth muscle is normally quiescent then it is likely that increases in hormones such as oxytocin, as might occur through sexual stimulation, enhance the effectiveness of such pacemaking until phasic contractile activity emerges.
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Affiliation(s)
- Fernanda S. Gravina
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, The University of Newcastle, Callaghan, NSW, Australia
| | - Dirk F. van Helden
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, The University of Newcastle, Callaghan, NSW, Australia
| | - Karen P. Kerr
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, The University of Newcastle, Callaghan, NSW, Australia
| | - Ramatis B. de Oliveira
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, The University of Newcastle, Callaghan, NSW, Australia
| | - Phillip Jobling
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, The University of Newcastle, Callaghan, NSW, Australia
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8
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Darios ES, Seitz B, Watts SW. Smooth Muscle Pharmacology in the Isolated Virgin and Pregnant Rat Uterus and Cervix. J Pharmacol Exp Ther 2012; 341:587-96. [DOI: 10.1124/jpet.111.191031] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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9
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Crankshaw DJ, Morrison JJ. Methodology and pharmacological analysis of effects of uterotonic compounds in human myometrium in vitro. Am J Obstet Gynecol 2011; 205:155.e1-6. [PMID: 21600545 DOI: 10.1016/j.ajog.2011.03.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 02/22/2011] [Accepted: 03/08/2011] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The methodology used to evaluate contractile effects of uterotonic agents in human myometrium in vitro varies. The are no studies evaluating the reliability of these commonly used techniques. STUDY DESIGN Myometrial strips (n=72) were exposed to 3 known uterotonic agents: oxytocin, U46619, and phenylephrine. The negative log of the molar concentration of the agonist that produces a half-maximal response (pEC50) and maximal response values were obtained, and compared, when either amplitude or mean force was used as indices of contraction. All data were expressed as a percentage of KCl elicited actvity. RESULTS Using pEC50 measurements, the order of potency was oxytocin greater than U46619 greater than phenylephrine for both indices, whereas the order of maximal response varied between mean force and amplitude. The coefficient of variation was lowest for pEC50 measurements, highest for maximal force estimations, and overall was 10-48% between, and 2-27% within, donor samples. CONCLUSION These findings support the use of pEC50 measurements for in vitro experiments using uterotonic agents and outline the variability that occurs for such myometrial experiments.
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Lust EB, Barthold C, Malesker MA, Wichman TO. Human Health Hazards of Veterinary Medications: Information for Emergency Departments. J Emerg Med 2011; 40:198-207. [DOI: 10.1016/j.jemermed.2009.09.026] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 08/28/2009] [Accepted: 09/19/2009] [Indexed: 11/30/2022]
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11
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Tong D, Lu X, Wang HX, Plante I, Lui E, Laird DW, Bai D, Kidder GM. A dominant loss-of-function GJA1 (Cx43) mutant impairs parturition in the mouse. Biol Reprod 2009; 80:1099-106. [PMID: 19176884 DOI: 10.1095/biolreprod.108.071969] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Expression of GJA1 (commonly known as connexin43 or Cx43), a major myometrial gap junction protein, is upregulated before the onset of delivery, suggesting an essential role for Cx43-mediated gap junctional intercellular communication (GJIC) in normal uterine contraction during parturition. To determine how a disease-linked Cx43 mutation affects myometrial function, we studied a mutant mouse model carrying an autosomal dominant mutation (Gja1(Jrt)) in the gene encoding Cx43 that displays features of the human genetic disease oculodentodigital dysplasia. We found that Cx43 level, specifically the phosphorylated species of the protein, is significantly reduced in the myometrium of the mutant mice (Gja1(Jrt)/+), as revealed by Western blotting and immunostaining. Patch-clamp electrophysiological measurements demonstrated that coupling between myometrial smooth muscle cells is reduced to <15% of wild-type, indicating that the mutant protein acts dominantly on its wild-type counterpart. The phosphorylated species of Cx43 in the mutant myometrium failed to increase prior to parturition as well as in response to exogenous estrogen. Correspondingly, in vitro experiments with uterine strips revealed weaker contraction of the mutant myometrium and reduced responsiveness to oxytocin, providing an explanation for the prolonged gestation and presence of suffocated fetuses in the uteri that were observed in some of the mutant mice. We conclude that the Gja1(Jrt) mutation has a dominant-negative effect on Cx43 function in the myometrium, severely reducing GJIC, leading to impaired parturition.
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Affiliation(s)
- Dan Tong
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, Ontario, Canada
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12
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Wray S, Noble K. Sex hormones and excitation-contraction coupling in the uterus: the effects of oestrous and hormones. J Neuroendocrinol 2008; 20:451-61. [PMID: 18266942 DOI: 10.1111/j.1365-2826.2008.01665.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this review, we examine how far the increased understanding that we have of the events in excitation contraction can explain the effects of the oestrous cycle and sex hormones on uterine function. Observational studies of electrical and mechanical activity in the rat myometrium have shown a relative quiescence during pro-oestrous, with little propagation of any electrical events. Thus, uterine activity can be said to approximately inversely reflect plasma 17beta-oestradiol concentrations. We show that Ca(2+) signalling and mechanical activity are greatest in metoestrous and dioestrous compared to pro-oestrous and oestrous. These data are discussed in terms of hormonal effects on Ca(2+) and K(+) channels. Finally, the influence of sex hormones on lipid rafts and caveolae are considered and discussed in relation to recent findings on their role in uterine signalling and contractility, and cholesterol levels and obesity.
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Affiliation(s)
- S Wray
- The Physiological Department, School of Biomedical Sciences, University of Liverpool, Liverpool, UK.
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Kitazawa T, Hirama R, Masunaga K, Nakamura T, Asakawa K, Cao J, Teraoka H, Unno T, Komori SI, Yamada M, Wess J, Taneike T. Muscarinic receptor subtypes involved in carbachol-induced contraction of mouse uterine smooth muscle. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2007; 377:503-13. [DOI: 10.1007/s00210-007-0223-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Accepted: 11/14/2007] [Indexed: 11/30/2022]
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Guerrero JA, Navarro-Nuñez L, Lozano ML, Martínez C, Vicente V, Gibbins JM, Rivera J. Flavonoids inhibit the platelet TxA(2) signalling pathway and antagonize TxA(2) receptors (TP) in platelets and smooth muscle cells. Br J Clin Pharmacol 2007; 64:133-44. [PMID: 17425630 PMCID: PMC2000638 DOI: 10.1111/j.1365-2125.2007.02881.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
AIMS Flavonoids may affect platelet function by several mechanisms, including antagonism of TxA(2) receptors (TP). These TP are present in many tissues and modulate different signalling cascades. We explored whether flavonoids affect platelet TP signalling, and if they bind to TP expressed in other cell types. METHODS Platelets were treated with flavonoids, or other selected inhibitors, and then stimulated with U46619. Similar assays were performed in aspirinized platelets activated with thrombin. Effects on calcium release were analysed by fluorometry and changes in whole protein tyrosine phosphorylation and activation of ERK 1/2 by Western blot analysis. The binding of flavonoids to TP in platelets, human myometrium and TPalpha- and TPbeta-transfected HEK 293T cells was explored using binding assays and the TP antagonist (3)H-SQ29548. RESULTS Apigenin, genistein, luteolin and quercetin impaired U46619-induced calcium mobilization in a concentration-dependent manner (IC(50) 10-30 microm). These flavonoids caused a significant impairment of U46619-induced platelet tyrosine phosphorylation and of ERK 1/2 activation. By contrast, in aspirin-treated platelets all these flavonoids, except quercetin, displayed minor effects on thrombin-induced calcium mobilization, ERK 1/2 and total tyrosine phosphorylation. Finally, apigenin, genistein and luteolin inhibited by >50% (3)H-SQ29548 binding to different cell types. CONCLUSIONS These data further suggest that flavonoids may inhibit platelet function by binding to TP and by subsequent abrogation of downstream signalling. Binding of these compounds to TP occurs in human myometrium and in TP-transfected HEK 293T cells and suggests that antagonism of TP might mediate the effects of flavonoids in different tissues.
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Affiliation(s)
- José A Guerrero
- Unit of Haematology and Clinical Oncology, Centro Regional de Hemodonación, University of Murcia, Murcia, Spain
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