Intracellular Ca2+ homeostasis in rat round spermatids.
Biol Cell
; 90(5): 391-8, 1998 Sep.
Article
em En
| MEDLINE
| ID: mdl-9835013
Intracellular calcium, [Ca2+]i, can regulate meiotic progression of mammalian oocytes. However, the role of [Ca2+]i in the regulation of the spermatogenic process and its cellular homeostatic mechanisms in spermatogenic cells has not been elucidated. Using intracellular fluorescent probes for Ca2+ and immunodetection of plasma membrane (PM) Ca(2+)-ATPases, we report that: a) rat round spermatids maintain [Ca2+]i levels of 60 +/- 5 nM (SEM), as estimated with fluo-3 in single cells or fura-2 in cells in suspension; b) these cells regulate [Ca2+]i by actively extruding it using a PM Ca(2+)-ATPase; c) rat spermatids also actively transport Ca2+ by sarco-endoplasmic reticulum type ATPases (SERCA); d) rat spermatids possess non-mitochondrial intracellular Ca2+i stores insensitive to thapsigargin but releasable by ionomycin; and e) rat spermatids do not activate Ca2+ entry mechanisms by the release of Ca2+ from SERCA-regulated stores. These results demonstrate that rat round spermatids can generate modulated intracellular Ca2+ signals upon activation of Ca2+ channels or Ca2+ release from intracellular stores.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Espermátides
/
Cálcio
/
Sinalização do Cálcio
/
Homeostase
Limite:
Animals
Idioma:
En
Revista:
Biol Cell
Ano de publicação:
1998
Tipo de documento:
Article
País de afiliação:
Chile
País de publicação:
Reino Unido