BACKGROUND:: Opiate abuse is a chronic relapsing disorder, and maintaining prolonged
abstinence remains a major challenge. Protracted abstinence is characterized by lowered
mood, and clinical studies show elevated comorbidity between addiction and depressive
disorders. At present, their relationship remains unclear and has been little studied in animal
models. Here we investigated emotional alterations during protracted abstinence, in mice
with a history of chronic morphine exposure. METHODS:: C57BL6J mice were exposed to a …