Fig. 5.

MMPIP raises basal cAMP levels and fails to effectively block l-AP4-mediated inhibition of cAMP accumulation. A, MMPIP induced a concentration-dependent increase in cAMP accumulation in mGluR7/HEK cells (EC₅₀ = 690 ± 130 nM). B, in contrast to blockade obtained in the presence of 100 μM concentration of the orthosteric antagonist LY341495 (●), a 1 μM concentration of MMPIP (□) increased basal cAMP levels but did not effectively block l-AP4-mediated inhibition of cAMP accumulation (compared maximal blockade to curve of l-AP4 alone, ■). Data represent the mean ± S.E.M. of three independent experiments performed in triplicate.