Table 3

Emax and EC50 values for WIN55,212-2-stimulated [35S]GTPγS binding

RegionTreatmentEC50Emax
nM fmol/mg
HippocampusVehicle979  ± 2983.52  ± 0.11
Δ9-THC851  ± 2611.11  ± 0.093-a 3-c
WIN55,212-21320  ± 4382.14  ± 0.193-a 3-d
Substantia nigraVehicle515  ± 466.54  ± 0.36
Δ9-THC963  ± 953-a 5.22  ± 0.383-b
WIN55,212-2769  ± 1205.74  ± 0.29

Effect of chronic cannabinoid treatment on the potency and maximal effect of WIN55,212-2 for stimulation of [35S]GTPγS binding was determined by generating concentration-effect curves in sections containing hippocampus and substantia nigra. EC50 andEmax values were calculated from individual concentration effect curves generated for each mouse, and values shown represent mean ± S.E.M. from eight mice in each treatment group.

  • ↵3-a  p < 0.01,

  • ↵3-b  p < 0.05 different from vehicle by Tukey-Kramer test;

  • ↵3-c  p < 0.01 different from WIN55,212-2-treated by Tukey-Kramer test;

  • ↵3-d  p < 0.01 different from Δ9-THC-treated by Tukey-Kramer test.