Figure 6.
Effect of PSNCBAM-1 and SR141716A on either (a) 10 nM CP55,940 or (b) 1 μM AEA-stimulated inhibition of cAMP accumulation induced by 5 μM forskolin, in HEK293-hCB1 cells. Agonist concentrations used were determined by their EC90 values. Cells were incubated with compounds for 30 min at room temperature. Intracellular cAMP levels were subsequently measured using the AlphaScreen kits from Perkin Elmer Inc. Data are means±s.e.m. from three experiments. The direct effects of PSNCBAM-1 and SR141716A on forskolin-induced cAMP responses were investigated as part of the validation of this assay and although some effects were noted, in particular with SR141716A, they did not alter the data interpretation when the agonist CP55,940 was present. AEA, arachidonoyl ethanolamide; HEK, human embryonic kidney; PSNCBAM-1, 1-(4-chlorophenyl)-3-[3-(6-pyrrolidin-1-ylpyridin-2-yl)phenyl]urea; SR141716A, N-(piperidin-1-yl)-5-(4-cholrophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide.