PDE10A and schizophrenia: MP-10, 2-[4-(1-methyl-4-pyridin-4-yl-1H-pyrazol-3-yl)-phenoxymethyl]-quinoline, an analog of papaverine with excellent potency (IC50 = 1.26 nM) and selectivity for PDE10A, was found to dose-dependently increase striatal cAMP and cGMP levels in CF-1 mice, and to improve negative symptoms and cognitive function in schizophrenia-like animal models [11].