CRIP1a does not affect ligand-induced desensitization of CB1R-mediated G-protein activation in CB1-HEK cells. Cells were pretreated for 4 hours with 10 μM WIN55,212-2 (WIN), 6 μM THC, or vehicle prior to harvesting and preparation of membranes. Varying concentrations of MAEA were incubated with membranes prepared from the indicated cell lines in the presence of 100 mM NaCl, 10 μM GDP, and 0.1 nM [35S]GTPγS, as described in Materials and Methods. Data are mean percentage stimulation ± S.E.M. (n = 4). No CRIP1a, no transfection of CRIP1a; CRIP1a, stable transfection of CRIP1a.