Effects of aromatase inhibition on spatial working memory and hippocampal astrocyte numbers

• Nélida María Conejo Jiménez ^[1] ; Héctor González Pardo ^[1] ; José Ignacio Arias ; Jorge Luis Arias Pérez ^[1]
  1. [1] Universidad de Oviedo

     Universidad de Oviedo

     Oviedo, España

     
• Localización: Revista iberoamericana de psicología y salud, ISSN 2171-2069, Vol. 3, Nº. 1, 2012, págs. 1-18
• Idioma: inglés
• Enlaces
  • Texto completo
• Resumen
  • español

    Se sabe que las hormonas sexuales inducen la diferenciación sexual del cerebro durante el desarrollo temprano en mamíferos. La testosterona secretada por los machos ya durante la gestación está tradicionalmente asociada con la diferenciación sexual cerebral y conductual, gracias a su conversión a estradiol por el enzima aromatasa. Sin embargo, hay evidencia de que la inhibición de la aromatasa puede también deteriorar las funciones cognitivas en mujeres que reciben tratamiento hormonal para el cáncer de mama. Con el fin de estudiar los efectos de la aromatasa en el cerebro y la conducta, ratas prepúberes macho y hembra tratadas prenatalmente con anastrozol y durante el desarrollo temprano fueron evaluadas en una prueba de memoria de trabajo espacial. Los resultados muestran que el tratamiento con anastrozol deterioró claramente la memoria de trabajo en machos y hembras en comparación con grupos tratados con vehículo y control. Además, el número de astrocitos que expresaron la proteína glial fibrilar ácida (GFAP) disminuyó en el área CA3 del hipocampo dorsal sólo en ratas macho. Estos resultados indican que la aromatasa juega un papel complejo en la diferenciación sexual del cerebro y afecta a la memoria espacial en machos y hembras.

  • English

    Sex hormones are known to induce the sexual differentiation of the brain during early development in mammals. Testosterone secreted by males already during gestation is classically believed to contribute to brain and behavioural sexual differentiation thanks to its conversion to estradiol by the enzyme aromatase. However, there is evidence suggesting that aromatase inhibition may also impair cognitive functions in women receiving hormonal treatment for breast cancer. In order to evaluate the effects of aromatase on brain and behaviour, male and female prepubescent rats treated with anastrozole prenatally and during early postnatal development were tested in a spatial working memory task. Results show that anastrozole treatment clearly impaired spatial working memory in male and female rats as compared to sex-matched vehicle-treated and control groups. In addition, the number of astrocytes expressing glial fibrillary acidic protein (GFAP) decreased in the CA3 area of the dorsal hippocampus only in male rats. These results indicate that aromatase plays a complex role on the sexual differentiation of the brain and affects spatial memory in males and females.

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