Why Are Females More Sensitive to the Effects of Cocaine?
Previous research has shown that females report more intense highs from cocaine use than do males, and that the former are more likely to become addicted to the drug, given the presence of the female hormone estradiol. However, little is known about how estradiol contributes to these differences.
New research supported by the National Institute on Drug Abuse (NIDA) may provide an answer. In examining why females are more sensitive to the rewarding/motivational effects of cocaine than their male counterparts, the study suggests that estradiol has the capacity to activate a particular receptor called MGluR5. This causes neurons to release more endocannabinoid neurotransmitters into the brain’s reward system, an effect that has previously been linked to stronger responses to cocaine among other stimulant drugs.
Commenting on the role played by estradiol in the greater sensitivity to cocaine use experienced by females, the conclusion reached, then, is that the hormone “mediates enhanced escalation of drug administration and greater europhia” via the mGluR5 and cannabinoid CBIR pathways.