title: Intracellular levels of hydrogen peroxide and nitric oxide in oocytes at various stages of meiotic cell cycle and apoptosis.
abstract: The objective was to find out the functional roles of hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) during various stages of meiotic cell cycle and apoptosis in rat oocytes. For this purpose, 30 oocytes from each stage such as diplotene, metaphase-I (M-I), metaphase-II (M-II) and apoptosis were collected and intracellular H(2)O(2), total nitrite level and inducible nitric oxide synthase (iNOS) expression were analysed. This study demonstrated that generation of a tonic level of H(2)O(2) induces meiotic resumption in diplotene-arrested oocytes and further increase may lead to apoptosis. Conversely, reduction in iNOS expression and total nitrite level are associated with meiotic resumption in diplotene-arrested oocytes, but induce apoptosis in aged oocytes. These results suggest that generation of a tonic level of H(2)O(2), reduced iNOS expression and total nitrite level are associated with meiotic resumption, while more generation of H(2)O(2) and sustained reduced total nitrite level are linked with oocyte apoptosis in rat.
authors.affiliation: Department of Zoology, Banaras Hindu University, Varanasi, India.
authors.forename: Anima
authors.initials: A
authors.lastname: Tripathi
authors.forename: Sabana
authors.initials: S
authors.lastname: Khatun
authors.forename: A N
authors.initials: AN
authors.lastname: Pandey
authors.forename: S K
authors.initials: SK
authors.lastname: Mishra
authors.forename: Radha
authors.initials: R
authors.lastname: Chaube
authors.forename: T G
authors.initials: TG
authors.lastname: Shrivastav
authors.forename: S K
authors.initials: SK
authors.lastname: Chaube
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002453:Cell Cycle / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D016922:Cellular Senescence / Q000502:physiology; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D008540:Meiosis / Q000502:physiology*; D009569:Nitric Oxide / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D009865:Oocytes / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D051381:Rats
chemical_list: D009569:Nitric Oxide; D006861:Hydrogen Peroxide; D052247:Nitric Oxide Synthase Type II