Figure 7. Adolescent ethanol exposure significantly decreases ethanol and allopregnanolone-induced facilitation of the tonic GABA_AR current in adult PrL-C.

A) Representative traces showing the change in I_hold in layer V pyramidal neurons in response to bath application of ethanol (10 mM, 50 mM and 100 mM) in PrL-C slices obtained from control and AIE exposed rats. B) Bath application of ethanol resulted in a dose-dependent facilitation of the tonic current, especially at higher doses (n = 15 cells/dose, p < 0.0001). The enhancement of tonic current that occurred with bath application of 50 and 100 mM ethanol was significantly attenuated in slices obtained from AIE exposed rats compared to slices from control rats (n = 6-10 cells/group for each dose; *p < 0.05, ***p < 0.001). C) Comparison of ethanol facilitation of the tonic current to the average THIP current in control and AIE exposed conditions indicates that AIE did not alter the affinity of the δ-GABA_AR to acute alcohol and instead reduced the efficacy of facilitation of tonic currents. D) Representative traces showing the change in I_hold in layer V pyramidal neurons in response to bath application of a low (0.1 μM) and high (1.0 μM) dose of the allopregnanolone in PrL-C slices obtained from control and AIE exposed adult rats E) Allopregnanolone dose-dependently facilitated the tonic current (n = 18 cells/dose, p = 0.0009), and this enhancement was significantly attenuated in slices obtained from AIE exposed rats compared to slices from control rats (n = 8-9 cells/group for each dose, *p < 0.05). F) Comparison of allopregnanolone facilitation of the tonic current to the average THIP current in control and AIE exposed conditions indicates that AIE did not alter the affinity of the δ-GABA_AR tonic current to acute allopregnanolone and instead reduced the efficacy of facilitation.