Research Paper Volume 8, Issue 11 pp 2848—2861
No effect of testosterone on behavior in aged Wistar rats
- 1 Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia
- 2 Institute of Physiology, Faculty of Medicine, Comenius University, 813 72 Bratislava, Slovakia
- 3 Institute of Pathophysiology, Faculty of Medicine, Comenius University, 811 08 Bratislava, Slovakia
- 4 Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, 842 15 Bratislava, Slovakia
- 5 Biomedical Research Center, Slovak Academy of Sciences, 831 01 Bratislava, Slovakia
- 6 Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, 842 15 Bratislava, Slovakia
Received: May 24, 2016 Accepted: October 28, 2016 Published: November 12, 2016
https://doi.org/10.18632/aging.101096How to Cite
Abstract
In men, aging is accompanied by a gradual decline in androgen secretion. Studies suggest beneficial effects of endogenous and exogenous testosterone on affective behavior and cognitive functions. The aim of this study was to describe behavioral and cognitive sex differences and to analyze the effects of long-term androgen deficiency in aged male rats. Thirty-months old rats divided into three groups (males, females and males gonadectomized as young adults) underwent a battery of behavioral tests assessing locomotor activity, anxiety, memory, anhedonia, sociability and depression-like behavior. No major effect of gonadectomy was found in any of the analyzed behavioral measures in male rats. The only consistent sex difference was confirmed in depression-like behavior with longer immobility time observed in males. In an interventional experiment, a single dose of testosterone had no effect on gonadectomized male and female rats in the forced swim test. In contrast to previous studies this comprehensive behavioral phenotyping of aged rats revealed no major role of endogenous testosterone. Based on our results long-term hypogonadism does not alter the behavior of aged male rats, neither does acute testosterone treatment. Whether these findings have any consequences on androgen replacement therapy in aged men remains to be elucidated.