Fig. 9

Males exhibit stronger ILC-NAcSh glutamatergic neurotransmission, while females display increased MSN intrinsic excitability. A Neurons in the infralimbic cortex (ILC) in both female and male mice were transfected with an eYFP-labeled AAV expressing channelrhodopsin, and the terminals in the shell of the nucleus accumbens (NAcSh) were optogenetically stimulated ex vivo. The shaded area in the enlarged box indicates recording area. Representative traces of the measured optogenetic local field potentials (oLFPs) in both female (B) and male (C) mice are presented at light stimulation durations of 1 ms (ms) (B: female, light red; C: male, light blue) and 4 ms (B female, dark red; C male, dark blue). D At all stimulus frequencies, males (blue) exhibited a significantly greater glutamatergic response (p = 0.002) than females (red). E Whole-cell current clamp recordings were measured in medium-spiny neurons (MSNs) in NAcSh. The shaded area in the enlarged box indicates recording area. Representative current clamp recordings of female (F) and male G NAcSh MSNs at 160 pA (top) and 200 pA (bottom) depolarizations are presented. Input current elicited significantly more action potentials in females than in males at 160 pA (F top) and 200 pA (F bottom), indicated by the asterisk. H Females (red) exhibited significantly greater intrinsic firing frequencies than males (blue) in response to current injection (p = 0.0489), and post hoc analysis indicated significant differences at 160 pA through 200 pA (p < 0.05). I Females (red) had significantly increased NAcSh MSN action potential firing frequency at maximum current injection (+ 220 pA) compared to males (blue) (p = 0.0435). NAcSh, nucleus accumbens shell; ac, anterior commissure; AAV, AAV adeno-associated virus; ILC infralimbic cortex