- Immunohistochemical analysis of ryanodine receptors during Bufo arenarum oocyte maturation and activation.

AJMAT MT, BONILLA F, HERMOSILLA C, ZELARAYÁN L., BÜHLER MI

Tafí del Valle Tucumán

Jornada; XXVI Annual Scientific Meeting Tucuman Biology Assocoation; 2011

Asociación de iología de Tucumán

IMMUNOHISTOCHEMICAL ANALYSIS OF RYANODINE RECEPTORS DURING  BUFO ARENARUM OOCYTE MATURATION AND ACTIVATION Ajmat, M.T., Bonilla F.; Hermosilla C.; Zelarayán, L.; Buhler; M.I. Instituto de Biología ? Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461? Tucumán  mtajmat@fbqf.unt.edu.ar   Transient increases in the concentration of cytosolic calcium are essential for triggering egg activation events. Increase of calcium results from its release from intracellular stores, mainly mediated by one or both intracellular calcium channels: the inositol trisphosphate receptor (IP3R) and the ryanodine receptor (RyR). We have previously reported the effect of specific RyR agonists and antagonists into mature Bufo arenarom oocytes. The aim of this work was to analyze RyR expression in immature, mature and activated Bufo arenarum oocytes by immunohistochemistry. Using a mouse monoclonal antibody against RyR (34C-SIGMA) we could confirm the existence of RyRs in Bufo arenarum oocytes. Results showed different patterns of distribution of the RyRs at different functional stages, suggesting a correlation with ultrastructural modifications of the endoplasmic reticulum and cortical granules during oocyte maturation and activation.