CALRETININ-POSITIVE CAJAL-RETZIUS CELLS PERSIST IN THE ADULT HUMAN NEOCORTEX

THE occurrence of Cajal-Retzius (CjRe) cells was studied in four corti cal areas of five normal adult humans using antibodies against calreti nin. Calretinin immunofluorescence and autofluorescence of lipofusin g ranules in CjRe cells were visualized by dual channel confocal laser s canning microscopy. Three types of CjRe cells existed in the adult hum an cortex: horizontal, triangular and multipolar, and their number did not decrease with ageing. Horizontal CjRe cells were found in all cor tical areas; they contained no lipofusin or less than other cells. Tri angular CjRe cells with descending dendrites were less numerous. Multi polar CjRe cells were rare and contained more lipofuscin. We conclude that calretinin-immunoreactivity can be used to study CjRe cell morpho logy in normal and diseased adult human brain.