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001-es BibID:	BIBFORM038801
035-os BibID:	PMID:15950414
Első szerző:	Borkó Rezső
Cím:	Slow motility, electromotility and lateral wall stiffness in the isolated outer hair cells / Rezső Borkó, Tamás József Batta, István Sziklai
Dátum:	2005
ISSN:	0378-5955
Megjegyzések:	Slow motile length changes of isolated, apical turn outer hair cells (OHCs) (n=36) were induced by perfusion of saline (flow rate: 0.6 microl/min) as a mechanical challenge or by perfusion of 12.5 mM KCl solution for 90 s as a chemical and mechanical challenge with and without ocadaic acid (OA), a serine/threonine protein phosphatase inhibitor. Electromotility was evoked by square pulses from +/-35 mV to +/-240 mV during the slow shortening and recovery period (n=36). Stiffness of the lateral wall was measured by the micropipette aspiration technique (n=20). Saline perfusion caused a reversible shortening of 774+/-87 nm (n=9) as well as K+ of 1465+/-159 nm (n=9). Slow shortening increased lateral wall stiffness (1.25+/-0.02 to 1.52+/-0.03 nN/microm) (n=5-5). Simultaneously, electromotility magnitude decreased (n=9). Ocadaic acid blocked slow shortening, increased lateral wall stiffness, and decreased the magnitude of electromotility. Mechanical or mechanical+chemical stimulation of ocadaic acid treated OHCs do not further change stiffness or electromotility. Isolated OHCs respond with slow shortening and consutive cell stiffness increase to mechanical insult. This phenomenon seems operating with calcium-, and phosphorylation-dependent modifications of the cytoskeletal proteins. The subsequent electromotility gain decrease suggests a slow OHC shortening driven regulation of the cochlear amplifier with simultaneous safety control of the auditory periphery against overstimulation.
Tárgyszavak:	Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban egyetemen (Magyarországon) készült közlemény
Megjelenés:	Hearing Research. - 207 : 1-2 (2005), p. 68-75. -
További szerzők:	Batta József Tamás (1970-) (fül-orr-gégész) Sziklai István (1954-) (fül-orr-gégész)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM038800
035-os BibID:	PMID:16092549
Első szerző:	Borkó Rezső
Cím:	Electromotile performance of isolated outer hair cells during slow motile shortening / Rezső Borkó, Tamás József Batta, István Sziklai
Dátum:	2005
ISSN:	0001-6489
Megjegyzések:	The electromotile performance of isolated OHCs does not seem to be dependent on slow motile shortening alone; other mechanisms, such as phosphorylation, are also involved. OBJECTIVE: To elucidate the relationship between the magnitude of electromotile displacements and magnitude of slow motile shortening of outer hair cells (OHCs) induced by mechanical or chemical stimulation over a reversible range. MATERIAL AND METHODS: Isolated guinea pig OHCs were mechanically (0.6 microl/min perfusion of saline; n =4) or chemically and mechanically (0.6 microl/min perfusion of 12.5 mM KCl; n =4) stimulated in a glass microchamber to evoke slow motile shortening. RESULTS: Combined mechanical and chemical stimulation evoked greater OHC shortening than mechanical stimulation alone. Both forms of stimulation resulted in reversible shortening. Electromotility was measured using low voltage (+/- 35 mV) and higher voltage (up to +/- 240 mV) electrical pulses mimicking the receptor potential at different stages of cell shortening. The magnitude of electromotility decreased simultaneously with slow motile shortenings of OHCs. Irrespective of the character of the stimulus (mechanical or mechanical + chemical), the decrease in the magnitude of electromotility was dependent on the degree of cell shortening. Ocadaic acid, a protein phosphatase inhibitor, blocked slow motility and decreased the magnitude of electromotility.
Tárgyszavak:	Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban egyetemen (Magyarországon) készült közlemény
Megjelenés:	Acta Oto-Laryngologica. - 125 : 5 (2005), p. 547-551. -
További szerzők:	Batta József Tamás (1970-) (fül-orr-gégész) Sziklai István (1954-) (fül-orr-gégész)
Internet cím:	Szerző által megadott URL Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon: