Investigation the Effect of Sexual Pheromones of Female Rat on Testosterone Plasma Levels of Infant, Mature and Old Male Wistar Rat

Pheromones are the chemical matters which secreted from animals and act for regulating animal populations and their social interactions. Mammals sexual pheromones cause various behaviors such as aggressive behaviors, acceleration in puberty, courtship behavior, sexual partner finding, paternal behaviors and pregnancy failing. In this research, we examined the effect of female rat pheromone on the male rat's plasma levels of testosterone in infancy, puberty and old age. By using special cage, we considered the effect of sexual pheromones without the interface of visual, auditory and tactile stimuli. We used ELIZA method for measurement plasma levels of testosterone in male rats. In 50-day male rats which were not placed next to the female rat (control group), the mean of plasma level of testosterone was 2.83 ng/ml that increased in 55-day (2.95 ng/ml), 60-day (3.03 ng/ml) and 65-day rats (3.58 ng/ml). In 85-day mature male rats which were not placed next to the female rat (control group), the mean of plasma level of testosterone was 7.67 ng/ml that increased in 90-day (8.23 ng/ml), 95-day (9.18 ng/ml) and 65-day rats (10.49 ng/ml). This increasing in p < 0.05 was significant. Although the plasma level of testosterone decrease among of old age (7.77 ng/ml) but in comparison to experimental groups of 150-day (8.83 ng/ml) and 160-day old rats (9.16 ng/ml) that receive female pheromones, plasma levels of testosterone were increase significantly. This finding indicate that female sexual pheromones increase the plasma level of testosterone and reproductive activities in infancy, puberty and old age periods of male rats life cycle.