Fentanyl self-administration is accelerated by methamphetamine co-use and results in worsened hypodopaminergia in male, but not female rats.

ABSTRACT: Combined use of fentanyl and methamphetamine (FENT + METH) has increased in recent years and has been documented in a growing number overdose deaths each year. The impact of FENT + METH on behavior and neurobiology is not well understood. In this study, male and female Long Evans rats were tested on a limited access, fixed ratio 1 self-administration schedule for increasing doses (1.25-5 μg/kg/infusion; iv) of fentanyl, with and without a single dose (0.1 mg/kg/infusion; iv) of methamphetamine, for 15 days. FENT + METH abolished dose responsiveness to fentanyl in all rats and accelerated intake in males, resulting in patterns of responding that may be more likely to result in adverse effects. Ex vivo slice voltammetry in the nucleus accumbens core showed decreases in dopamine release and r

SUBMITTER: Dawes MH 

PROVIDER: S-EPMC11484618 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature