Effects of classic antidepressants on [3H]CDP-diacylglycerol accumulation. Tissue slices prepared from indicated brain regions were prelabeled with [3H]cytidine and incubated with various concentrations of either imipramine (IMI), desipramine (DES), fluoxetine (FLU), paroxetine (PAR), maprotiline (MAP), or nomifensine (NOM). After 90 min, tissue contents of [3H]CDP-diacylglycerol were assayed. Each bar is the mean ± SEM (N = 9). Each drug stimulated significant concentration-dependent accumulations of CDP-diacylglycerol (ANOVA, p < 0.001 for each drug). Based on posthoc Dunnett tests, all agents induced statistically significant CDP-diacylglycerol responses at the 3 or 10 μM concentrations, except for paroxetine in the hippocampus and imipramine in the striatum where the drug effects were not significant until the 30 μM and higher concentrations.