Physiol. Res. 52: 189-194, 2003

The Effect of Ovarian Hormones on Antioxidant Enzyme Activities in the Brain of Male Rats


Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences and 1Department of Physiology, Institute of Biological Research “Siniša Stanković”, Belgrade, Serbia, Yugoslavia

Received February 27, 2002
Accepted May 31, 2002

The brain is widely responsive to gonadal hormones. The functional significance of ovarian hormones in the brain is evident from biochemical studies indicating that estradiol or progesterone treatment of testectomized rats produces changes of antioxidant enzyme activities. The effect of estradiol benzoate (EB) and progesterone (P) in the control of antioxidant (AO) enzyme activities was studied in the brain of adult male Wistar rats. The activities of catalase (CAT), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) and glutathione reductase (GR) were measured in appropriate subcellular fractions, prepared from brains of animals belonging to various experimental groups. These groups were designed with the intention to follow changes in enzyme activities 2 h or 24 h after systemic administration of 5 g EB or 2 mg P to testectomized (TX) animals. The obtained results show that both EB and P increase CAT activity, whereas EB decreases GSH-Px, GST and GR activities. These findings clearly show the modulatory role of EB and P in the control of enzymes responsible for the protection of rat nerve cells against oxidative damage caused by free oxygen radicals.

Key words
Brain • Antioxidant enzymes • Estradiol • Progesterone • Rats

Reprint requests
Dr. S.B. Pajović, Laboratory of Molecular Biology and Endocrinology, Vinča Institute of Nuclear Sciences, 11000 Belgrade, Serbia, Yugoslavia. Fax: 381-11-455-561. e-mail:

© 2003 by the Institute of Physiology, Czech Academy of Sciences