Figure 1.

The cannabinoid receptor agonist WIN 55,212-2 (WIN) ((R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate) induces long-term depression (LTD) in the nucleus accumbens (NAc) of adolescent but not adult mice. Graphs show the time course of the effect of WIN (1 µM), applied for 15 minutes in the perfusion solution at the time indicated by the black bar, on the mean (±SEM) amplitude of the field excitatory postsynaptic potentials/population spike (fEPSP/PS) measured in the NAc (a-b). Data is expressed as a percentage of baseline fEPSP/PS in n=8 slices from adolescent mice (a) and n=9 slices from adult mice (b). Insets show records of fEPSP/PSs measured in 2 slices at the time points indicated on the graphs, that is, before (1) and 50 to 60 minutes after (2) perfusion with WIN. Average magnitude of WIN-induced inhibition measured 55 to 60 minutes after the start of the perfusion of WIN in slices from adolescent (white bar) and adult (black bar) mice (c). ** P<.01 compared with baseline (paired Student’s t test); # P<.05 (unpaired Student’s t test). Protein levels of β-actin (d) and cannabinoid type 1 receptor (CB1) (e) in the NAc of adolescent (n=12) and adult (n=8) mice expressed as a percentage of the levels measured in adolescent mice. ## P<.01 (unpaired Student’s t test).