Melatonin protects against the effects of chronic stress on sexual behaviour in male rats.
The effects of chronic mild stress (CMS) on both sexual behaviour and wet dog shakes (WDS), a serotonergic type 2A (5-HT2A) receptor-mediated behaviour, were explored in the male rat. In addition, the possible attenuation of these effects by chronic treatment with melatonin, a putative 5-HT2A antagonist, was examined. The CMS procedure resulted in a significant increase in WDS and an overall decrease in all aspects of sexual behaviour. Concurrent melatonin administration attenuated the CMS-induced effects on sexual behaviour, but not the effects on either spontaneous WDS or WDS in response to the 5-HT2A agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane, suggesting a mechanism of action other than exclusive 5-HT2A antagonism. These results are the first to demonstrate that melatonin significantly protects against the detrimental effects of a chronic stressor on sexual behaviour.
Brotto
L A
LA
Department of Psychology, 2136 West Mall, Vancouver, BC, Canada V6T 1Z4.
Gorzalka
B B
BB
LaMarre
A K
AK
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008550:Melatonin / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D020318:Rats, Long-Evans; D012726:Sexual Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological / Q000188:drug therapy* / Q000503:physiopathology
D000975:Antioxidants; D008550:Melatonin