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1.

001-es BibID:BIBFORM043635
Első szerző:Izumi, Hiroko
Cím:Membrane Hyperpolarization by Sperm-Activating and -Attracting Factor Increases cAMP Level and Activates Sperm Motility in the Ascidian Ciona intestinalis / Hiroko Izumi, Teréz Márián, Kazuo Inaba, Yoshitaka Oka, Masaaki Morisawa
Dátum:1999
ISSN:0012-1606
Megjegyzések:In the ascidian Ciona intestinalis (and C. savignyi), sperm-activating and -attracting factor (SAAF) is released from the egg at fertilization and stimulates both Ca(2+) influx and a transient increase in cAMP level of the sperm, leading to the activation of sperm motility (M. Yoshida et al., 1994, Dev. Growth Differ. 36, 589-595). In this paper we show in C. intestinalis that valinomycin, a potassium-selective ionophore, as well as SAAF, activated sperm motility, and this activation was suppressed by extracellular high K(+). Membrane potential measurements showed that both SAAF and valinomycin increase K(+) permeability of sperm and induce membrane hyperpolarization, the amplitude of which depends on the external K(+) concentration. The membrane potential and intracellular K(+) concentration of Ciona sperm without SAAF were estimated to be about -50 mV and 560 +/- 40 mM, respectively. After treatment with SAAF or valinomycin the membrane potential became almost equal to the equilibrium potential of K(+) (-100 mV), and the cAMP level increased in artificial seawater. A potent voltage-dependent K(+) channel blocker, MCD peptide, at the concentration of 10 microM blocked SAAF-induced hyperpolarization of the cells, increase in cAMP, and sperm motility. These results suggest that membrane hyperpolarization produced by the opening of K(+) channels elevates cAMP synthesis and leads to the activation of sperm motility in Ciona.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Developmental Biology. - 213 : 2 (1999), p. 246-256. -
További szerzők:Márián Teréz (1950-) (radiobiológus) Inaba, Kazuo Oka, Yoshitaka Morisawa, Masaaki
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DOI
Intézményi repozitóriumban (DEA) tárolt változat
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2.

001-es BibID:BIBFORM038939
Első szerző:Krasznai Zoltán (biofizikus)
Cím:Membrane hyperpolarization removes inactivation of Ca2+ channels, leading to Ca2+ influx and subsequent initiation of sperm motility in the common carp / Krasznai, Z., Marian, T., Izumi, H., Damjanovich, S., Balkay, L., Tron, L., Morisawa, M.
Dátum:2000
Megjegyzések:Change of osmolality surrounding spawned sperm from isotonic to hypotonic causes the initiation of sperm motility in the common carp. Here we show that membrane-permeable cAMP does not initiate motility of carp sperm that is quiescent in isotonic solution, and that motility of the demembranated sperm can be reactivated without cAMP. Furthermore, the cAMP level does not change during the initiation of sperm motility, and inhibitors of protein kinase do not affect sperm motility, suggesting that no cAMP-dependent system is necessary for the regulation of sperm motility. Sperm motility could not be initiated in Ca(2+)-free hypoosmotic solutions, and significant increase in the intracellular Ca(2+) level was observed by a Ca-sensitive fluorescence dye during hypoosmolality-induced active motion period. The demembranated sperm cells were fully reactivated in the solutions containing 10(-7) to 10(-5) M Ca(2+). Ca(2+) channel blockers such as verapamil and omega-conotoxin reversibly inhibited the initiation of sperm motility, suggesting that Ca(2+) influx is the prerequisite for the initiation of carp sperm motility. Motility of intact sperm was completely blocked; however, that of the demembranated sperm was not inhibited by the calmodulin inhibitor W7, suggesting that the calmodulin bound close to the plasma membrane participated in the initiation of sperm motility. Flow cytometric membrane potential measurements and spectrophotometric measurements by using fluorescence dyes showed transient membrane hyperpolarization on hypoosmolality-induced motility. This article discusses the role of membrane hyperpolarization on removal of inactivation of Ca(2+) channels, leading to Ca(2+) influx at the initiation of carp sperm motility.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Proceedings of the National Academy of Sciences of the United States of America. - 97 : 5 (2000), p. 2052-2057. -
További szerzők:Márián Teréz (1950-) (radiobiológus) Izumi, Hiroko Damjanovich Sándor (1936-2017) (biofizikus) Balkay László (1963-) (biofizikus) Trón Lajos (1941-) (biofizikus) Morisawa, Masaaki
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
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3.

001-es BibID:BIBFORM004730
Első szerző:Krasznai Zoltán (biofizikus)
Cím:Gadolinium, a mechano-sensitive channel blocker, inhibits osmosis-initiated motility of sea- and freshwater fish sperm, but does not affect human or ascidian sperm motility / Krasznai, Z., Morisawa, M., Krasznai, Z. T., Morisawa, S., Inaba, K., Bazsane Kassai Z., Rubovszky, B., Bodnar, B., Borsos, A., Marian, T.
Dátum:2003
ISSN:886-1544 (Print)
Megjegyzések:Exposure to hypo-osmotic or hyperosmotic environment triggers the initiation of fish sperm motility. In this article, we report that calcium and potassium channel blockers do not influence motility of puffer fish sperm but calmodulin antagonists reversibly decrease it, suggesting that calmodulin-Ca(2+) interactions are prerequisite for the initiation of sperm motility in this species. Gadolinium (a stretch activated ion channel blocker) decreased the motility of puffer fish sperm from 92 +/- 3% to 6 +/- 3% and that of carp sperm from 91 +/- 7% to 3.5 +/- 4.3% in a dose-dependent manner (10-40 micro M). The effect of gadolinium was reversible, suggesting that stretch activated ion channels participate in the initiation of sperm motility of the two species. Gadolinium inhibits changes in the isoelectric point of certain proteins of puffer fish sperm, which occur when sperm motility is initiated in a hypertonic solution. Anisotropy measurements showed that hypo-osmotic treatment, which initiates carp sperm motility, increased membrane fluidity. When hypo-osmotic treatment was given in the presence of gadolinium, the sperm membrane remained as rigid as in quiescent cells, while motility was blocked. By contrast, gadolinium did not influence the motility parameters of Ciona or human sperm. Based on these lines of evidence, we suggest that conformational changes of mechanosensitive membrane proteins are involved in osmolality-dependent but not osmolality-independent sperm
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Animals
Biophysics
Calcium
Carps
Cells
Ciona intestinalis
Dose-Response Relationship,Drug
drug effects
Gadolinium
Human
Humans
Hungary
Ion Channel Gating
Ion Channels
Male
Membrane Fluidity
Membrane Proteins
metabolism
Osmotic Pressure
pharmacology
physiology
Potassium
Potassium Channel Blockers
Proteins
Research
Sperm Motility
Support
Takifugu
Megjelenés:Cell Motility and the Cytoskeleton. - 55 : 4 (2003), p. 232-243. -
További szerzők:Morisawa, Masaaki Krasznai Zoárd Tibor (1973-) (szülész-nőgyógyász, gyermeknőgyógyász) Morisawa, Sachiko Inaba, Kazuo Bazsáné Kassai Zsuzsa (1946-) (embriológus) Rubovszky Bálint (1975-) (élettanász) Bodnár B. Borsos Antal (1939-) (szülész-nőgyógyász, gyermeknőgyógyász) Márián Teréz (1950-) (radiobiológus)
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4.

001-es BibID:BIBFORM004731
Első szerző:Krasznai Zoltán (biofizikus)
Cím:Role of ion channels and membrane potential in the initiation of carp sperm motility / Krasznai, Z., Morisawa, M., Morisawa, S., Krasznai, Z. T., Tron, L., Gaspar, R., Marian, T.
Dátum:2003
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Ion Channels
Sperm Motility
Megjelenés:Aquatic living resources [electronic resource]. - 16 : 5 (2003), p. 445-449. -
További szerzők:Morisawa, Masaaki Morisawa, Sachiko Krasznai Zoárd Tibor (1973-) (szülész-nőgyógyász, gyermeknőgyógyász) Trón Lajos (1941-) (biofizikus) Gáspár Rezső (1944-) (biofizikus) Márián Teréz (1950-) (radiobiológus)
Internet cím:DOI
elektronikus változat
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5.

001-es BibID:BIBFORM005087
Első szerző:Krasznai Zoltán (biofizikus)
Cím:Role of the Na+/Ca2+ exchanger in calcium homeostasis and human sperm motility regulation / Krasznai, Z., Krasznai, Z. T., Morisawa, M., Bazsane Kassai Z., Hernadi, Z., Fazekas, Z., Tron, L., Goda, K., Marian, T.
Dátum:2006
ISSN:886-1544 (Print)
Megjegyzések:A number of cell functions, such as flagellar beating, swimming velocity, acrosome reaction, etc., are triggered by a Ca2+ influx across the cell membrane. For appropriate physiological functions, the motile human sperm maintains the intracellular free calcium concentration ([Ca2+]i) at a submicromolar level. The objective of this study was to determine the role of the Na+/Ca2+ exchanger (NCX) in the maintenance of [Ca2+]i in human spermatozoa. Spermatozoa maintained in extracellular medium containing>or=1 microM Ca2+ exhibited motility similar to that of the control. In addition to several calcium transport mechanisms described earlier, we provide evidence that the NCX plays a crucial role in the maintenance of [Ca2+]i. Three chemically unrelated inhibitors of the NCX (bepridil, DCB (3',4'-dichlorobenzamil hydrochloride), and KB-R7943) all blocked human sperm motility in a dose and incubation time dependent manner. The IC50 values for bepridil, DCB, and KB-R7943 were 16.2, 9.8, and 5.3 microM, respectively. The treatment with the above-mentioned blockers resulted in an elevated [Ca2+]i and a decreased [Na+]i. The store-operated calcium channel (SOCC) inhibitor SKF 96365 also blocked the sperm motility (IC50=2.44 microM). The presence of the NCX antigen in the human spermatozoa was proven by flow cytometry, confocal laser scanning microscopy, and immunoblotting techniques. Calcium homeostasis of human spermatozoa is maintained by several transport proteins among which the SOCC and the NCX may play a major role.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
analogs and derivatives
Bepridil
Biophysics
Calcium
Calcium Channel Blockers
Calcium Channels
Cell Membrane
Dose-Response Relationship,Drug
drug effects
Enzyme Inhibitors
Flow Cytometry
Homeostasis
Human
Humans
Hungary
Immunoblotting
Male
Membrane Potentials
metabolism
Microscopy
Microscopy,Confocal
pharmacology
physiology
Proteins
Research
Sodium-Calcium Exchanger
Sperm Motility
Spermatozoa
Support
Thapsigargin
Thiourea
ultrastructure
Megjelenés:Cell Motility and the Cytoskeleton. - 63 : 2 (2006), p. 66-76. -
További szerzők:Krasznai Zoárd Tibor (1973-) (szülész-nőgyógyász, gyermeknőgyógyász) Morisawa, Masaaki Bazsáné Kassai Zsuzsa (1946-) (embriológus) Hernádi Zoltán (1948-) (szülész-nőgyógyász, klinikai onkológus) Fazekas Zsolt (1971-) (biofizikus) Trón Lajos (1941-) (biofizikus) Goda Katalin (1969-) (biofizikus) Márián Teréz (1950-) (radiobiológus)
Internet cím:DOI
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6.

001-es BibID:BIBFORM005095
Első szerző:Shiba, K.
Cím:Na+/Ca2+ exchanger modulates the flagellar wave pattern for the regulation of motility activation and chemotaxis in the ascidian spermatozoa / Shiba, K., Marian, T., Krasznai, Z., Baba, S. A., Morisawa, M., Yoshida, M.
Dátum:2006
ISSN:886-1544 (Print)
Megjegyzések:Ion channels and ion exchangers are known to be important participants in various aspects of sperm physiology, e.g. motility activation, chemotaxis, the maintenance of motility and the acrosome reaction in the sperm. We report here on a role of the K+ -independent Na+/Ca2+ exchanger (NCX) on ascidian sperm. Reverse-transcriptase PCR reveals that the NCX is expressed in the testis while immunoblotting and immunolocalization demonstrate that the NCX exists on the sperm in the ascidian Ciona savignyi and C. intestinalis. A potent blocker of the NCX, KB-R7943 was found to block sperm-activating and -attracting factor (SAAF)-induced motility activation, sperm motility and sperm chemotaxis. We further analyzed the effects of this blocker on motility parameters such as the flagellar waveform, curvature, beat frequency, amplitude and wavelength of the sperm flagella. Inhibition of the NCX caused two distinct effects: a low concentration of KB-R7943 induced symmetric bending, whereas a high concentration of KB-R7943 resulted in asymmetric flagellar bending. These findings suggest that the NCX plays important roles in the regulation of SAAF-induced sperm chemotaxis, motility activation and motility maintenance in the ascidian. This study provides new information toward an understanding of Ca2+ transport systems in sperm motility and chemotaxis.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
analogs and derivatives
Animals
antagonists and inhibitors
Anti-Arrhythmia Agents
Calcium
Calcium Channel Blockers
Chemotaxis
drug effects
Immunoblotting
Ion Channels
Male
metabolism
pharmacology
physiology
Research
Sodium-Calcium Exchanger
Sperm Motility
Sperm Tail
Spermatozoa
Support
Thiourea
Urochordata
Megjelenés:Cell Motility and the Cytoskeleton. - 63 : 10 (2006), p. 623-632. -
További szerzők:Márián Teréz (1950-) (radiobiológus) Krasznai Zoltán (1950-) (biofizikus) Baba, S. A. Morisawa, Masaaki Yoshida, Manabu
Internet cím:DOI
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7.

001-es BibID:BIBFORM004330
Első szerző:Yoshida, Kaoru
Cím:Functional implications of membrane modification with semenogelins for inhibition of sperm motility in humans / Yoshida K., Krasznai Z. T., Krasznai Z., Yoshiike M., Kawano N., Yoshida M., Morisawa M., Tóth Z., Bazsáné Kassai Z., Márián T., Iwamoto T.
Dátum:2009
Megjegyzések:Semenogelin I and II (Sgs) are the major component of human semen coagulum. The protein is rapidly cleaved after ejaculation by a prostate-specific antigen, resulting in liquefaction of the semen coagulum and the progressive release of motile spermatozoa. Sgs inhibit human sperm motility; however, there is currently no information on its effect on the sperm membrane. This study investigated the role of Sgs on human sperm motility through regulation of membrane potential and membrane permeability. Fresh semen samples were obtained from normozoospermic volunteers, and studies were conducted using motile cells selected using the swim-up method. Sgs changed the characteristics of sperm motion from circular to straightforward as evaluated by a computer-assisted motility analyzer, and all parameters were decreased more than 2.5 mg/mL. The results demonstrate that Sgs treatment immediately hyperpolarized the membrane potential of swim-up-selected sperm, changed the membrane structure, and time-dependently increased membrane permeability, as determined through flow cytometric analysis. The biphasic effects of Sgs were time- and dose-dependent and partially reversible. In addition, a monoclonal antibody against Sgs showed positive binding to cell membrane proteins in fixed cells, observed with confocal fluorescence microscopy. These results demonstrate that Sgs modifies the membrane structure, indirectly inhibiting motility, and provides suggestions for a therapy for male infertility through selection of a functional sperm population using Sgs.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cell Motility and the Cytoskeleton 66 : 2 (2009), p. 99-108. -
További szerzők:Krasznai Zoárd Tibor (1973-) (szülész-nőgyógyász, gyermeknőgyógyász) Krasznai Zoltán (1950-) (biofizikus) Yoshiike, Miki Kawano, Natsuko Yoshida, Manabu Morisawa, Masaaki Tóth Zoltán (1948-) (szülész-nőgyógyász, humángenetikus) Bazsáné Kassai Zsuzsa (1946-) (embriológus) Márián Teréz (1950-) (radiobiológus) Iwamoto, Teruaki
Internet cím:elektronikus változat
DOI
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