FGF19 and type 1 diabetes mellitus: In neurons from T1DM mice, FGF19 decreased mean evoked action potential frequency at the 10, 15, and 20 pA current steps (Figure 2J; n = 26; 10pA, p = 0.0314; 15 pA, p = 0.0135; 20 pA, p = 0.0408).