||The uptake of calcium (Ca++) into cerebellar granule cells in primary culture was increased by depolarizing the cells with either 60 mM KC1 or veratridine. Nitrendipine, at concentrations of 100 nM or greater, antagonized approximately 40 percent of the depolarization induced Ca++ uptake. The half maximal concentration of nitrendipine was 7nM. Furthermore, another dihydropyridine derivative, BAY K 8644 enhanced the uptake of Ca++ and in the presence of nitrendipine, this facilitation of Ca++ uptake was reduced. Thus, these data indicate the existence of voltage dependent Ca++ channels which are sensitive to dihydropyridines in primary cultures of cerebellar granule cells.