Fig. 7.

Effects of U50,488 on LHb neuronal excitability were absent following MD. A-B. Example traces of AP generation in response to +50 pA current application at baseline (black) and 30min post- U50,488 (red). U50,488 did not significantly alter the number of AP generated across depolarizing current steps of A. Ih- neurons or B. Ih+ neurons in MD rats. C. Scatter plot of Ih currents recorded from LHb neurons across non-MD (grey) and MD (white) rats (non-MD, Ih-: n = 19/14; MD, Ih-: n = 8/7; non-MD, Ih+: n = 15/12; MD, Ih+: n = 12/10). There was no significant difference in the mean amplitude of Ih currents in Ih+ LHb neurons between non-MD and MD rats. D. At baseline, MD Ih- neurons had larger Rin compared to MD Ih+ neurons. E. U50,488 significantly lowered AP thresholds in both MD Ih- neurons and MD Ih+ neurons F. There was no effect of U50,488 on fAHPs in MD Ih- or MD Ih+ neurons. G. U50,488 significantly decreased mAHPs of both MD Ih- neurons and MD Ih+ neurons. *p < 0.05, **p < 0.01, ***p < 0.0001. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)