Women are generally more vulnerable to drug addiction than men, especially when it comes to cocaine.

This week, the Journal Nature Communications published a study conducted by researchers from the Icahn School of Medicine, at the Manhattan-based Mount Sinai Hospital, which revealed that hormonal fluctuations explain why women who try cocaine are more likely to get addicted than men. The researchers also concluded that women are more likely to start using cocaine at an earlier age and in larger quantities than men are; consequently, women display more difficulty remaining abstinent around cocaine than men.

Dr. Erin Calipari, the study’s lead author, explained that her team looked at both female and male mice throughout different stages of their main reproductive cycles because mice have the same dopamine pathways and responses to drugs as humans.

Calipari’s team observed that female mice going through their menstrual cycles that were exposed to cocaine experienced potentialized effects. “When the hormone levels [of female mice] were low they looked a lot like the male subjects,” she said. “When estrogen levels were really high, the rewarding effects of cocaine were greatly enhanced.”

The researchers noticed that the increased estrogen levels in females affected not only the quantity of dopamine released to their brain in response to the cocaine but how long the dopamine stayed active in their brain cells.

Although both female and male mice spent more time on the side of the cage previously paired with cocaine, female mice displayed higher place preference.   

“Addiction is really a multifaceted disorder,” Calipari said. “There are rewarding effects of the drug, but there’s a lot of other things that happen, too. Humans associate particular environments with the drug experience. These associations are really strong and if the relapse process is driven by environmental cues, we have to understand how to treat that. It may not be as easy as a pharmacological intervention.”

Since the female subjects responded to… (continue reading)