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Liu XM, Li J, Chen D, Li H, Qin XY, Wang YX, Gu YZ, Li N, Zhou LG, Feng M. Ano1 regulates embryo transport by modulating intracellular calcium levels in oviduct smooth muscle. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167059. [PMID: 38336104 DOI: 10.1016/j.bbadis.2024.167059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 01/26/2024] [Accepted: 02/03/2024] [Indexed: 02/12/2024]
Abstract
Oviductal smooth muscle exhibits spontaneous rhythmic contraction (SRC) and controls the passage of the ova at the exact time, but its mechanistic regulation remains to be determined. In this study, female mice with Ano1SMKO (smooth muscle-specific deletion of Ano1) had reduced fertility. Deficiency of Ano1 in mice resulted in impaired oviductal SRC function and reduced calcium signaling in individual smooth muscle cells in the oviduct. The Ano1 antagonist T16Ainh-A01 dose-dependently inhibited SRCs and [Ca2+]i in the oviducts of humans and mice. A similar inhibitory effect of SRCs and [Ca2+]i was observed after treatment with nifedipine. In our study, ANO1 acted primarily as an activator or amplifier in [Ca2+]i and contraction of tubal smooth muscle cells. We found that tubal SRC was markedly attenuated in patients with ectopic pregnancy. Then, our study was designed to determine whether chloride channel Ano1-mediated smooth muscle motility is associated with tubal SRC. Our findings reveal a new mechanism for the regulation of tubal motility that may be associated with abnormal pregnancies such as ectopic pregnancies.
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Affiliation(s)
- Xiao-Man Liu
- Central Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China; Central Laboratory, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, PR China; Institute of Clinical Microbiology, Shandong Academy of Clinical Medicine, Jinan, Shandong 250021, PR China
| | - Juan Li
- Department of Obstetrics and Gynecology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Defang Chen
- Office of Operation Management Committee, Central Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250013, PR China
| | - Hao Li
- Department of Blood Transfusion, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Xiao-Yan Qin
- Department of Obstetrics and Gynecology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Yun-Xia Wang
- Department of Obstetrics and Gynecology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Yong-Zhong Gu
- Department of Obstetrics and Gynecology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Na Li
- Department of Obstetrics and Gynecology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Li-Guang Zhou
- Department of Ultrasound, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China
| | - Mei Feng
- Central Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, PR China; Central Laboratory, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, PR China; Institute of Clinical Microbiology, Shandong Academy of Clinical Medicine, Jinan, Shandong 250021, PR China.
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2
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Yuan S, Wang Z, Peng H, Ward SM, Hennig GW, Zheng H, Yan W. Oviductal motile cilia are essential for oocyte pickup but dispensable for sperm and embryo transport. Proc Natl Acad Sci U S A 2021; 118:e2102940118. [PMID: 34039711 PMCID: PMC8179221 DOI: 10.1073/pnas.2102940118] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Mammalian oviducts play an essential role in female fertility by picking up ovulated oocytes and transporting and nurturing gametes (sperm/oocytes) and early embryos. However, the relative contributions to these functions from various cell types within the oviduct remain controversial. The oviduct in mice deficient in two microRNA (miRNA) clusters (miR-34b/c and miR-449) lacks cilia, thus allowing us to define the physiological role of oviductal motile cilia. Here, we report that the infundibulum without functional motile cilia failed to pick up the ovulated oocytes. In the absence of functional motile cilia, sperm could still reach the ampulla region, and early embryos managed to migrate to the uterus, but the efficiency was reduced. Further transcriptomic analyses revealed that the five messenger ribonucleic acids (mRNAs) encoded by miR-34b/c and miR-449 function to stabilize a large number of mRNAs involved in cilium organization and assembly and that Tubb4b was one of their target genes. Our data demonstrate that motile cilia in the infundibulum are essential for oocyte pickup and thus, female fertility, whereas motile cilia in other parts of the oviduct facilitate gamete and embryo transport but are not absolutely required for female fertility.
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Affiliation(s)
- Shuiqiao Yuan
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557;
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zhuqing Wang
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557
- Sections of Metabolic Diseases and Translational Genomics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA 90502
| | - Hongying Peng
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557
| | - Sean M Ward
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557
| | - Grant W Hennig
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557
| | - Huili Zheng
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557
- Sections of Metabolic Diseases and Translational Genomics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA 90502
| | - Wei Yan
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557;
- Sections of Metabolic Diseases and Translational Genomics, The Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA 90502
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095
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Qian J, Chen Q, Ward SM, Duan E, Zhang Y. Impacts of Caffeine during Pregnancy. Trends Endocrinol Metab 2020; 31:218-227. [PMID: 31818639 PMCID: PMC7035149 DOI: 10.1016/j.tem.2019.11.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 11/10/2019] [Accepted: 11/12/2019] [Indexed: 12/19/2022]
Abstract
Epidemiological studies have revealed that caffeine consumption during pregnancy is associated with adverse gestational outcomes, yet the underlying mechanisms remain obscure. Recent animal studies with physiologically relevant dosages have begun to dissect adverse effects of caffeine during pregnancy with respect to oviduct contractility, embryo development, uterine receptivity, and placentation that jointly contribute to pregnancy complications. Interestingly, caffeine's effects are highly variable between individual animals under well-controlled experimental settings, suggesting the possibility of epigenetic regulation of these phenotypes, in addition to genetic variants. Moreover, caffeine exposure during sensitive windows of pregnancy may induce epigenetic changes in the developing fetus or even the germ cells to cause adult-onset diseases in subsequent generations. We discuss these research frontiers in light of emerging data.
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Affiliation(s)
- Jingjing Qian
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qi Chen
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, CA 92521, USA
| | - Sean M Ward
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV 89557, USA
| | - Enkui Duan
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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4
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Tubal muscles determine embryo implantation site; prognosis of ectopic pregnancy at chronic functional disorders. Med Hypotheses 2019; 132:109332. [DOI: 10.1016/j.mehy.2019.109332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 07/22/2019] [Accepted: 07/25/2019] [Indexed: 11/20/2022]
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5
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Qian J, Zhang Y, Qu Y, Zhang L, Shi J, Zhang X, Liu S, Kim BH, Hwang SJ, Zhou T, Chen Q, Ward SM, Duan E, Zhang Y. Caffeine consumption during early pregnancy impairs oviductal embryo transport, embryonic development and uterine receptivity in mice. Biol Reprod 2019; 99:1266-1275. [PMID: 29982366 DOI: 10.1093/biolre/ioy155] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 07/03/2018] [Indexed: 12/14/2022] Open
Abstract
Caffeine consumption has been widely used as a central nervous system stimulant. Epidemiological studies, however, have suggested that maternal caffeine exposure during pregnancy is associated with increased abnormalities, including decreased fertility, delayed conception, early spontaneous abortions, and low birth weight. The mechanisms underlying the negative outcomes of caffeine consumption, particularly during early pregnancy, remain unclear. In present study, we found that pregnant mice treated with moderate (5 mg/kg) or high (30 mg/kg) dosage of caffeine (intraperitoneally or orally) during preimplantation resulted in retention of early embryos in the oviduct, defective embryonic development, and impaired embryo implantation. Transferring normal blastocysts into the uteri of caffeine-treated pseudopregnant females also showed abnormal embryo implantation, thus indicating impaired uterine receptivity by caffeine administration. The remaining embryos that managed to implant after caffeine treatment also showed increased embryo resorption rate and abnormal development at mid-term stage, and decreased weight at birth. In addition to a dose-dependent effect, significant variations between individual mice under the same caffeine dosage were also observed, suggesting different sensitivities to caffeine, similar to that observed in human populations. Collectively, our data revealed that caffeine exposure during early pregnancy impaired oviductal embryo transport, embryonic development, and uterine receptivity, which are responsible for abnormal implantation and pregnancy loss. The study raises the concern of caffeine consumption during early stages of pregnancy.
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Affiliation(s)
- Jingjing Qian
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yunfang Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA.,University of Chinese Academy of Sciences, Beijing, China
| | - Yongcun Qu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Liwen Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Junchao Shi
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Xudong Zhang
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Shichao Liu
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Bo Hyun Kim
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Sung Jin Hwang
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Tong Zhou
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Qi Chen
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Sean M Ward
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Enkui Duan
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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6
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Myosalpinx Contractions Are Essential for Egg Transport Along the Oviduct and Are Disrupted in Reproductive Tract Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:265-294. [DOI: 10.1007/978-981-13-5895-1_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Ahmed AH, Maulood IM. The roles of potassium channels in contractile response to urotensin-II in mercury chloride induced endothelial dysfunction in rat aorta. IRANIAN JOURNAL OF VETERINARY RESEARCH 2018; 19:208-216. [PMID: 30349568 PMCID: PMC6184028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Revised: 02/17/2018] [Accepted: 03/03/2018] [Indexed: 06/08/2023]
Abstract
Urotensin-II (U-II), the most potent vasoconstrictor that has recently been recognized as a new candidate in cardiovascular dysfunction, might exert vasoconstriction through, at least partially, potassium channels that are predominant in both endothelial and vascular smooth muscle cells (VSMCs). The present study was designed to evaluate the roles of potassium channels in vascular responses to U-II in intact and mercury induced endothelial dysfunction in rat aorta. The study involved pre-incubation of rat aortic rings with potassium channels blockers: charybdotoxin (chtx), tetraethylammonium (TEA), barium chloride (BaCl2), glibenclamide, 4-aminopyridine (4-AP) and clotrimazole. Then vascular responses to increased concentrations of human U-II (hU-II) were applied to each group in the presence and absence of mercury chloride (HgCl2). Urotensin-II efficacy was significantly increased in chtx, TEA and BaCl2 treated groups, while significantly decreased in glibenclamide and clotrimazole treated groups as compared with the control group. In the presence of mercury, hU-II efficacy was significantly changed in all groups except clotrimazole treated group. The novel findings were that potassium channels modulated the vascular contractile responses to hU-II in isolated rat aorta and mercury treatment increased hU-II efficacy and deteriorated potassium signaling.
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Affiliation(s)
- A. H. Ahmed
- Correspondence: A. H. Ahmed, Department of Biology, College of Science, Salahaddin University, Erbil, Iraq. E-mail:
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Ishikawa Y, Usui T, Yamashita M, Kanemori Y, Baba T. Surfing and Swimming of Ejaculated Sperm in the Mouse Oviduct1. Biol Reprod 2016; 94:89. [DOI: 10.1095/biolreprod.115.135418] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 03/04/2016] [Indexed: 12/19/2022] Open
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Mechanisms of beat-to-beat regulation of cardiac pacemaker cell function by Ca²⁺ cycling dynamics. Biophys J 2014; 105:1551-61. [PMID: 24094396 DOI: 10.1016/j.bpj.2013.08.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 07/08/2013] [Accepted: 08/15/2013] [Indexed: 01/31/2023] Open
Abstract
Whether intracellular Ca(2+) cycling dynamics regulate cardiac pacemaker cell function on a beat-to-beat basis remains unknown. Here we show that under physiological conditions, application of low concentrations of caffeine (2-4 mM) to isolated single rabbit sinoatrial node cells acutely reduces their spontaneous action potential cycle length (CL) and increases Ca(2+) transient amplitude for several cycles. Numerical simulations, using a modified Maltsev-Lakatta coupled-clock model, faithfully reproduced these effects, and also the effects of CL prolongation and dysrhythmic spontaneous beating (produced by cytosolic Ca(2+) buffering) and an acute CL reduction (produced by flash-induced Ca(2+) release from a caged Ca(2+) buffer), which we had reported previously. Three contemporary numerical models (including the original Maltsev-Lakatta model) failed to reproduce the experimental results. In our proposed new model, Ca(2+) releases acutely change the CL via activation of the Na(+)/Ca(2+) exchanger current. Time-dependent CL reductions after flash-induced Ca(2+) releases (the memory effect) are linked to changes in Ca(2+) available for pumping into sarcoplasmic reticulum which, in turn, changes the sarcoplasmic reticulum Ca(2+) load, diastolic Ca(2+) releases, and Na(+)/Ca(2+) exchanger current. These results support the idea that Ca(2+) regulates CL in cardiac pacemaker cells on a beat-to-beat basis, and suggest a more realistic numerical mechanism of this regulation.
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Kobori K, Maruta Y, Mineo S, Shigematsu T, Hirayama M. Polyphenol-Retaining Decaffeinated Cocoa Powder Obtained by Supercritical Carbon Dioxide Extraction and Its Antioxidant Activity. Foods 2013; 2:462-477. [PMID: 28239130 PMCID: PMC5302282 DOI: 10.3390/foods2040462] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 10/03/2013] [Accepted: 10/03/2013] [Indexed: 11/17/2022] Open
Abstract
Cocoa beans contain many functional ingredients such as theobromine and polyphenols, but also contain a relatively high amount of caffeine, which can negatively impact human health. It is therefore desirable to reduce caffeine levels in cocoa powder used to make chocolate or cocoa beverages while retaining functional ingredients. We have established conditions for supercritical carbon dioxide (SCCO₂) extraction that remove 80.1% of the caffeine from cocoa powder while retaining theobromine (94.1%) and polyphenols (84.7%). The antioxidant activity of the decaffeinated cocoa powder (DCP) made with this optimized SCCO₂ extraction method was 85.3% that of non-processed cocoa powder. The total procyanidin and total polyphenol concentrations of the DCPs resulting from various SCCO₂ extractions showed a significant positive correlation with oxygen radical absorbance capacity (ORAC). The correlation coefficient between total polyphenols and ORAC was higher than that between total procyanidins and ORAC; thus, the concentration of total polyphenols might be a greater factor in the antioxidant activity of DCP. These results indicate that we could remove large quantities of caffeine from conventional high-cocoa products while retaining the functional benefits of high polyphenol content. This SCCO₂ extraction method is expected to be applicable high-cocoa products, such as dark chocolate.
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Affiliation(s)
- Kinji Kobori
- Bourbon Institutes of Health, Bourbon Corporation, 4-2-14 Matsunami, Kashiwazaki City, Niigata 945-8611, Japan.
| | - Yuto Maruta
- Bourbon Institutes of Health, Bourbon Corporation, 4-2-14 Matsunami, Kashiwazaki City, Niigata 945-8611, Japan.
| | - Shigeru Mineo
- Bourbon Institutes of Health, Bourbon Corporation, 4-2-14 Matsunami, Kashiwazaki City, Niigata 945-8611, Japan.
| | - Toru Shigematsu
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata City, Niigata 956-8603, Japan.
| | - Masao Hirayama
- Bourbon Institutes of Health, Bourbon Corporation, 4-2-14 Matsunami, Kashiwazaki City, Niigata 945-8611, Japan.
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata City, Niigata 956-8603, Japan.
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Dixon RE, Britton FC, Baker SA, Hennig GW, Rollings CM, Sanders KM, Ward SM. Electrical slow waves in the mouse oviduct are dependent on extracellular and intracellular calcium sources. Am J Physiol Cell Physiol 2011; 301:C1458-69. [PMID: 21881003 DOI: 10.1152/ajpcell.00293.2011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spontaneous contractions of the myosalpinx are critical for oocyte transport along the oviduct. Slow waves, the electrical events that underlie myosalpinx contractions, are generated by a specialized network of pacemaker cells called oviduct interstitial cells of Cajal (ICC-OVI). The ionic basis of oviduct pacemaker activity is unknown. Intracellular recordings and Ca(2+) imaging were performed to examine the role of extracellular and intracellular Ca(2+) sources in slow wave generation. RT-PCR was performed to determine the transcriptional expression of Ca(2+) channels. Molecular studies revealed most isoforms of L- and T-type calcium channels (Cav1.2,1.3,1.4,3.1,3.2,3.3) were expressed in myosalpinx. Reduction of extracellular Ca(2+) concentration ([Ca(2+)](o)) resulted in the abolition of slow waves and myosalpinx contractions without significantly affecting resting membrane potential (RMP). Spontaneous Ca(2+) waves spread through ICC-OVI cells at a similar frequency to slow waves and were inhibited by reduced [Ca(2+)](o). Nifedipine depolarized RMP and inhibited slow waves; however, pacemaker activity returned when the membrane was repolarized with reduced extracellular K(+) concentration ([K(+)](o)). Ni(2+) also depolarized RMP but failed to block slow waves. The importance of ryanodine and inositol 1,4,5 trisphosphate-sensitive stores were examined using ryanodine, tetracaine, caffeine, and 2-aminoethyl diphenylborinate. Results suggest that although both stores are involved in regulation of slow wave frequency, neither are exclusively essential. The sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA) pump inhibitor cyclopiazonic acid inhibited pacemaker activity and Ca(2+) waves suggesting that a functional SERCA pump is necessary for pacemaker activity. In conclusion, results from this study suggest that slow wave generation in the oviduct is voltage dependent, occurs in a membrane potential window, and is dependent on extracellular calcium and functional SERCA pumps.
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Affiliation(s)
- Rose Ellen Dixon
- Dept. of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557, USA
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