Fig. 4.

Dose-effect functions for selective FAAH inhibitors alone (URB597, open inverted triangle, n = 3; AM4303, open diamond, n = 3) and in combination with 1.0 mg/kg selective MGL inhibitor AM4301 (URB597, closed circle, n = 3; AM4303, closed square, n = 3), administered in subjects trained to discriminate 0.01 mg/kg AM4054 from vehicle (V). Abscissae, cumulative dose, log scale; ordinate, percentage of responses on the AM4054-associated lever (top panel), response rate (bottom panel). Symbols left of abscissae break indicate performance during V and AM4054 (AM) control sessions. Points represent averages (±S.E.M.) for the groups of subjects.