|
Sex differences in Dextromethorphan-induced
behavioral and neurochemical toxicity in adolescent rats A high dose of dextromethorphan (DM), a widely using antitussive agent, has been found to be abused. Behavioral effects of DM were measured in adolescent rats since abusing DM usually starts during adolescent period. Nocturnal activity of the rat was measured after injection of DM (10, 20, 40 and 80 mg/kg, i.p.) at 20:30 on postnatal day 28. Spontaneous locomotor activity decreased in a dose-dependent manner after DM. Curiously, this effect was showed only in females but not in males. Three hours after DM, Fos-positive cells increased in the paraventricular nucleus in a dose-dependent manner, and this effect was obvious in females. When DM (40 mg/kg) was administered daily on postnatal days 28-37, locomotor activity increased on 10th day of treatment only in females. These female rats showed a behavioral sensitization on challenging DM after 7 days of drug-free period. Ten days' treatment with DM increased NMDAR1 immunoreactivities in the hypothalamus and the frontal cortex, again only in females. These data suggest that females are more sensitive to behavioral and neurochemical effects of DM during adolescent period. Keywords: Dextromethorphan, drug abuse, behavior, NMDAR1, sex difference |
|
|
|
|
|
|
|
|
|