Studies explain adolescents' vulnerability to addictive drugs
In two studies with mice and humans to be published together in the journal eLife , the investigators from Baylor College of Medicine, US, have found that the ability to produce (or synthesize) new proteins, regulated by the molecule eIF2, accounts for adolescents' hypersensitivity to both cocaine and nicotine. "In humans, adolescence, namely the period between the early teenage years and early twenties, is a time of heightened susceptibility to the effects of addictive drugs, but previous studies have struggled to explain why. Our studies support the idea that regulation of protein synthesis by eIF2 might be the underlying cause," says senior author Mauro Costa-Mattioli. In the first study, the team injected adolescent and adult mice with saline or a low dose of cocaine. Their results showed that in adolescents, but not adults, cocaine reduces the activity of eIF2α. This leads to an increase in the strength of the connections, or synapses, between dopamine-storin