Figure 7. 5-HT_2A-mediated head twitch behavior is attenuated in PSD-95^null mice.

(A) 5-HT_2A-mediated head twitch response after i.p. injection of 5 mg/kg DOI (N=11 littermate pairs) and 5-HT_1A-mediated hypothermic response after i.p. injection of 5 mg/kg 8-OH-DPAT (N=12 littermate pairs). There is a significant decrease in DOI-induced head twitch in PSD-95^null mice, in contrast with the magnitude of the decrease in core body temperature induced by 8-OH-DPAT, which is the same in both PSD-95^wildtype and PSD-95^null mice. (B), (C), and (D) Western blot and associated quantification for p-ERK1/2, ERK1/2, p-GSK3β, and GSK3β 15 minutes after i.p. injection of vehicle or DOI (N=4–5 littermate pairs). DOI induces pERK1/2 and pGSK3β in wildtype, but not null, mice. For quantification, p-ERK1/2 and p-GSK3β were normalized to ERK1/2 and GSK3β, respectively. Data are given as means +/− the SEM. ^*p < .05, ^**p < .01, ^***p < .001; one-tailed unpaired t-test.