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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)
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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
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