Figure 10.

CAR and DDCAR inhibit spontaneous dopamine neuronal firing in the rat SNc. (A) Dose–response effect of systemic CAR (n=9) and DDCAR (n=7) administration on firing of SNc dopamine neurons. Inhibition of firing activity of dopamine neurons by CAR was more substantial than the effect exerted by DDCAR. **P<0.01; ***P<0.001 vs vehicle by Dunnett’s post hoc test. (B) Inhibition of SNc dopamine firing by a single dose (applied at time=0 min) of CAR (10 µg/kg, i.v.; n=6) or DDCAR (120 µg/kg, i.v.; n=5). Note the long-lasting inhibitory action of DDCAR on neuronal firing. CAR data are also depicted in Delcourte et al.28 The number of recorded neurons is indicated by n.

Abbreviations: CAR, cariprazine; DDCAR, didesmethyl-cariprazine; E_max, maximal effect exerted by the drug; i.v., intravenous; nc, not calculable; SNc, substantia nigra pars compacta.