Adolescent intermittent ethanol exposure does not alter responsiveness to ifenprodil or expression of vesicular GABA and glutamate transporters

Abstract

Adolescent intermittent ethanol (AIE) exposure in the rat results in a retention of adolescent‐like responsiveness to ethanol into adulthood characterized by enhanced sensitivity to socially facilitating and decreased sensitivity to socially suppressing and aversive effects. Similar pattern of responsiveness to social and aversive effects of the selective glutamate NMDA NR2B receptor antagonist ifenprodil is evident in adolescent rats, suggesting that AIE would also retain this pattern of ifenprodil sensitivity into adulthood. Social (Experiment 1) and aversive (measured via conditioned taste aversion; Experiment 2) effects of ifenprodil were assessed in adult male and female rats following AIE exposure. Sensitivity to the social and aversive effects of ifenprodil was not affected by AIE exposure. Experiment 3 assessed protein expression of vesicular transporters of GABA (vGAT) and glutamate (vGlut2) within the prelimbic cortex and nucleus accumbens in adolescents versus adults and in AIE adults versus controls. vGlut2 expression was higher in adolescents relative to adults within the PrL, but lower in the NAc. AIE adults did not retain these adolescent‐typical ratios. These findings suggest that AIE is not associated with the retention of adolescent‐typical sensitivity to NR2B receptor antagonism, along with no AIE‐induced shift in vGlut2 to vGAT ratios.

Neuroplasticity and Multilevel System of Connections Determine the Integrative Role of Nucleus Accumbens in the Brain Reward System

“…Expression level of vesicular GABA transporter (vGAT) and vesicular glutamate transporter 2 (vGlut2) in NAc of the adolescent and adult rats after ethanol exposure shows a characteristic ontogenetic pattern with lower vGlut2/vGAT ratios in adolescents compared to adults [276]. The presented data suggest the constantly changing influence of excitatory (glutaminergic) and inhibitory (GABA-ergic) projections on NAc at various stages of ontogenetic development.…”

Binge eating promotes ethanol self-administration in female rats with a history of intermittent ethanol exposure at adolescence

“…The procedures endorsed the Declaration of Helsinki, the Guide for the Care and Use of Laboratory Animals as adopted by the NIH/EU and were approved by the Institutional Animal Care and Use Committee at INIMEC-CONICET-UNC. 1) IEA at adolescence Similar to Dannenhoffer et al (2021), the rats were administered every other day with ethanol (4.0 g/kg, intragastrical, concentration: 25% v/v, Porta Hnos, Córdoba, Argentina) or an equivalent volume of tap water, between PDs 25 and 45 (for a total of 11 administrations, see Figure 1), thus spanning the adolescent developmental stage (Burke and Miczek, 2014;Doremus-Fitzwater and Spear, 2016). The administration involved the introduction of polyethylene tubing, connected to a 10 ml syringe, into the oral cavity, which was then guided to the stomach.…”