Alterations of Amphetamine Reward by Prior Nicotine and Alcohol Treatment: The Role of Age and Dopamine

Evidence suggests that nicotine and alcohol can each serve as a gateway drug. We determined whether prior treatment would alter amphetamine reward. Also, we examined age dopaminergic neurotransmission are important in this regard. Male female adolescent adult C57BL/6J mice were tested for baseline place preference. Mice then received six conditioning with saline/nicotine (0.25 mg/kg) twice daily, followed by saline/ethanol (2 g/kg). Control conditioned saline/saline throughout. Finally, (3 mg/kg), once the nicotine-alcohol-paired chamber, preference 24 h later. The following day, challenged (1 under drugged state. immediately euthanized, their brain removed, nucleus accumbens isolated processed level of dopamine receptors transporter glutamate receptors. observed greater amphetamine-induced naïve adolescents than no change state-dependent between two groups. In contrast, induced significant but not nicotine-alcohol exposure drug-free was significantly adults enhanced response associated higher dopamine-transporter D1 reduced D2 receptors’ expression rather mice, changes levels. These results suggest differentially alters reward mice. Alterations may be involved phenotype.