Figure 1.

Anandamide activates outward currents in capsaicin-sensitive mouse trigeminal sensory neurons. Selected trigeminal neurons were voltage clamped at +40 mV, as described in Methods. Superfusion of AEA (100 μM) produced a slowly developing outward current that reversed slowly on wash. Subsequent superfusion of capsaicin produced a large, rapidly developing outward current in the same neuron. This experiment is typical of 56 small trigeminal neurons challenged with both AEA and capsaicin, five additional cells did not respond to either agonist.