INVESTIGADORES
JAHN Graciela Alma
artículos
Título:
Advancement of reproductive senescence and changes in the early expression of oestrogen, progesterone and µ-opioid receptors induced by neonatal hypoxia in the female rat.
Autor/es:
EZQUER ME; VALDEZ SR; SELTZER AM; JAHN GA
Revista:
BRAIN RESEARCH
Editorial:
Elsevier
Referencias:
Año: 2008 vol. 1214 p. 73 - 83
ISSN:
0006-8993
Resumen:
Perinatal hypoxia is a frequent birth complication, and although its early consequences on brain development have been well studied, few studies address any long-term effects. Postnatal insults producing small disturbances in endocrine function can have marked and long-lasting effects. In the present work we studied the effects of two types of perinatal brain injury: global hypoxia (H, 6.5 % O2 for 50 min) and hypoxia plus ischemia (HI, ligature of the right carotid artery) on female rat reproductive performance and expression of mediobasal hypothalamus-preoptic area (MBH-PO) estrogen, progesterone and µ opioid receptors at different times after injury, measuring the mRNA (by semiquantitative RT-PCR) and protein (by Western blot). H or HI advanced approximately 3 months the appearance of blunted preovulatory LH surges and cyclic irregularities (prolonged estrus) characteristic of the early stages of reproductive senescence. 48 h after H or HI we observed decreases in ERβ, µOR and PR (only in the H group) mRNAs and in total ER and µOR proteins, followed by increased PR levels (mRNA and protein) 7 days post-injury and by increased µOR protein and ERβ mRNA in the H group and ERα, ERβ and µOR mRNAs and ER protein in the HI group30 days post-injury. Thus, an episode of hypoxia suffered during early postnatal life induces premature reproductive senescence on the female rats, accompanied by early changes in some MBH-PO hormone receptors (µOR, ER and PR), whose expression is intimately involved in the regulation of gonadotrophin secretion and female sexual cyclicity..