Parvalbumin-like immunoreactivity of layer V pyramidal cells in the motor and somatosensory cortex of adult primates

Most previous immunocytochemical studies have indicated that the calcium-binding protein parvalbumin is present only in non-pyramidal neurons of the adult cerebral cortex. Using nickel and cobalt to enhance the diaminobenzidine reaction product, we observed large layer V pyramidal cells with parvalbumin-like immunoreactivity in the primary motor cortex (area 4) and somatosensory cortex of adult macaque monkeys and galagos, including giant Betz cells in area 4.