Figure 8. Suppression of insulin action on K⁺ currents following inhibition of MAP kinase action by compound PD98059.

A and B show the mean ( ± s.e.m.) I_t and I_ss densities, respectively (at +50 mV), in myocytes from control (n = 34) rats, and from STZ-treated rats in the absence of insulin (n = 19 cells), with insulin alone (n = 23), and with insulin in the presence of 25 μm PD98059 (n = 25). I_ss and I_K1 (not shown) were unchanged, whereas the enhancement of I_t by insulin was blocked by the inhibition of MAP kinase action.