Brain Tissue Oxidative Damage As a Possible Mechanism for the Deleterious Effect of a Chronic High Dose of Estradiol on Learning and Memory in Ovariectomized Rats; [Dano Oxidativo Ao Tecido Cerebral Como Possivel Mecanismo De Efeito Deleterio Da Alta Dose Cronica De Estradiol No Aprendizado E Memoria De Ratas Ooforectomizadas] Publisher Pubmed



Khodabandehloo F¹ ; Hosseini M² ; Rajaei Z³ ; Soukhtanloo M⁴ ; Farrokhi E² ; Rezaeipour M² Show Affiliations
Source: Arquivos de Neuro-Psiquiatria Published:2013

Abstract

In addition to antioxidative effects, estrogens also exert pro-oxidative actions. The effect of chronic administration of a high dose of estradiol valerate on Morris water maze tasks and brain tissues oxidative damage was investigated. The Sham-Est and OVX-Est groups were treated with estradiol valerate (4 mg/kg) for 12 weeks. Escape latency and traveled path in the Sham-Est and OVX-Est groups were significantly higher than in the Sham and OVX groups (p<0.01 and p<0.001). In the probe trial, the animals of the Sham-Est and OVX-Est groups spent lower time in Q1 compared to Sham and OVX groups (p<0.05 and p<0.001). In Sham-Est and OVX-Est groups, the brain tissue total thiol concentration was significantly lower, and malondialdehyde (MDA) concentrations were higher than in the Sham and OVX groups (p<0.05 and p<0.001). It is concluded that administration of high exogenous levels of estradiol impairs performance and enhances oxidative stress.