Fig. 4. Submicromolar concentrations of anandamide inhibit α_1H and α_1I currents but not α_1G currents. (A) Effects of increasing concentrations of anandamide on calcium currents generated by the α_1H subunit. (B) Time course of the inhibition of α_1H currents by increasing concentrations of anandamide. (C) Dose–response curves of anandamide for the three human cloned T-channels. The curves were fitted with a sigmoidal relationship where I/Icontrol = 1/(1 + 10^{[(LogEC50 – log[anandamide]) × Hillslope]}).