Progesterone induces calcium influx and acrosomal exocytosis in human sperm. Pharmacologic evidence suggests that voltage-dependent calcium channels (VDCCs) are involved. In this study, membrane potential (Vm) and intracellular calcium concentration ([Ca(2+)](i)) were monitored simultaneously to assess the effect of VDCC gating on the calcium influx triggered by progesterone. Holding the Vm to values that maintained VDCCs in a deactivated (-71 mV) closed state inhibited the calcium influx induced by progesterone by approximately 40%. At this Vm, the acrosomal reaction induced by progesterone, but not by A23187, was inhibited. However, when the Vm was held at -15 mV (which maintains VDCCs in an inactivated closed state), the progesterone-induced calcium influx was stimulated. Furthermore, the progesterone and voltage-dependent calcium influxes were additive. These findings indicate that progesterone does not produce VDCC gating in human sperm.
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http://dx.doi.org/10.1002/j.1939-4640.2004.tb02766.x | DOI Listing |
Chin J Integr Med
January 2025
Department of Ultrasound in Medicine, the Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China.
Objective: To evaluate the therapeutic effects of Kuanxiong Aerosol (KXA) on ischemic stroke with reperfusion and elucidate the underlying pharmacological mechanisms.
Methods: In vivo pharmacological effects on ischemic stroke with reperfusion was evaluated using the transient middle cerebral artery occlusion (t-MCAO) mice model. To evaluate short-term outcome, 30 mice were randomly divided into vehicle group (n=15) and KXA group (n=15).
Cells
December 2024
Department of Biology and Biochemistry, University of Houston, Houston, TX 77204, USA.
Podocytes express large-conductance Ca-activated K channels (BK channels) and at least two different pore-forming KCa1.1 subunit C-terminal splice variants, known as VEDEC and EMVYR, along with auxiliary β and γ subunits. Podocyte KCa1.
View Article and Find Full Text PDFEur J Orthod
December 2024
Division of Paediatric Dentistry & Orthodontics, Faculty of Dentistry, the University of Hong Kong, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, China.
Background: Periodontal ligament cells (PDLCs) possess mechanotransduction capability, vital in orthodontic tooth movement (OTM) and maintaining periodontal homeostasis. The study aims to elucidate the expression profiles of mechanosensitive ion channel (MIC) families in PDLCs and how the inflammatory mediator alters their expression and function, advancing the understanding of the biological process of OTM.
Methods And Methods: Human PDLCs were cultured and exposed to TNF-α.
Orphanet J Rare Dis
January 2025
Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, 6-1 Kishibe-Shimmachi, Suita, Osaka, 564-8565, Japan.
Background: Transient receptor potential cation channel subfamily V member 2 (TRPV2) functions as a stretch-sensitive calcium channel, with overexpression in the sarcolemma of skeletal and cardiac myocytes leading to detrimental calcium influx and triggering muscle degeneration. In our previous pilot study, we showed that tranilast, a TRPV2 inhibitor, reduced brain natriuretic peptide levels in two patients with muscular dystrophy and advanced heart failure. Building on this, we performed a single-arm, open-label, multicenter study herein to evaluate the safety and efficacy of tranilast in the treatment of advanced heart failure in patients with muscular dystrophy.
View Article and Find Full Text PDFBiochim Biophys Acta Biomembr
January 2025
Department of Molecular Pathobiology, New York University, New York, NY, USA. Electronic address:
Inorganic polyphosphate (polyP) is a polymer that consists of a series of orthophosphates connected by high-energy phosphoanhydride bonds, like those found in ATP. In mammalian mitochondria, polyP has been linked to the activation of the mitochondrial permeability transition pore (mPTP). However, the details of this process are not completely understood.
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