The effects of rat strain, sex and THC on brain and behaviour : factors that alter the sensitivity to drugs of abuse

The laboratory rat has been used for over a century, and through directed and accidental mechanisms, different rat strains were developed. This study examined the effect of strain and sex on metrics of brain size and function and in response to amphetamine. In addition to strain and sex, the adolescent period is sensitive to drugs of abuse, such as marijuana. This study also examined the effects of post-pubertal exposure of the psychoactive component of marijuana, Δ9-tetrahydrocannabinol (THC), to males of females of two rat strains. Rats were assessed for developmental and adult differences in brain and behaviour, including alterations in sensitivity to amphetamine. This study also implemented parametric and nonparametric statistical tests. Strain and sex contributed to behavioural and neuroanatomical differences between groups exposed to THC during adolescence, and drug experience in adolescence produced strain- and sex-specific effects. This study highlights the background-dependent effects of THC on brain and behaviour