Figure 6. Peak maximal calcium transient. Shaded square = racemic ketamine (n = 10); black square = S(+)-ketamine (n = 10); open square = R(-)-ketamine (n = 10); mean +/- SD. Peak calcium transients were normalized according to the rundown of the FURA-2 signal (see Methods section). Significant differences of the comparison between increasing concentrations of either the isomers or the racemat with the initial control are shown (*P < 0.05).