No Significant Difference Between Intact and Testosterone Depleted or Administrated Male Rats in Spatial Learning and Memory

Androgens have been shown to affect cognitive aspects of spatial memory. Testosterone which is the most important androgen, plays a role in the organization of behavior during development. Also, it has been shown that androgens cause sex related differences in learning and memory especially during neonatal period. In the current study, we assessed the effects of castration and testosterone enanthate (TE) administration on spatial cognition. Multiple doses of testosterone enanthate (20, 40, 80 and 120 mg/Kg) were examined on different groups using Morris water maze. Spatial memory was preserved in castrated rats. There was also no difference among multiple doses and control groups. For control of the level of testosterone in the blood of casterated rats and intact rats, blood samples were collected from intact group and 7, 10, 12, 14, 21 days after casteration. Testosterone levels were measured by Radio-immuno assay (RIA) technique and compared among all groups. The level of testosterone after 7 days in casterated rats were 0 nmol/L and after 21 days were 0.02±0.02 nmol/L while in intact rats were 2.69±0.88 nmol/L. These data suggests that changes in the level of androgen in circulation have no effect on spatial localization, at least after puberty in male rats.