REGIONAL DIFFERENCE IN THE DISTRIBUTION OF PARVALBUMIN-CONTAINING NEURONS IMMUNOREACTIVE FOR MONOCLONAL-ANTIBODY HNK-1 IN THE MOUSE CEREBRAL-CORTEX

Using preembedding immunocytochemistry at light microscopic level, we found that, although monoclonal antibody HNK-1 selectively outlined a subpopulation of GABAergic neurons containing a specific calcium-bindi ng protein parvalbumin (PV) in the adult mouse cerebral cortex, the pr oportion of HNK-1-positive cells to PV-containing cells showed promine nt regional difference. In the parietal cortex, similar to 50% of PV-p ositive cells were HNK-1-positive whereas only similar to 10% of PV-po sitive cells were HNK-1-immunoreactive in the occipital and temporal c ortices. There were also prominent differences in this proportion amon g allocortical areas. These observations indicate that the cellular co mposition of chemically defined subpopulations of GABAergic neurons ar e different from area to area in mouse cerebral cortex.