Effect of various substances on colchicine uptake by cells sensitive and resistant to it

The effect of various substances on the uptake of [³H]colchicine by L and L-53 cells, resistant to colcemid and colchicine was investigated. Vinblastin, to which L-53 cells possess cross resistance, increases accumulation of labeled colchicine in L cells threefold, and in L-53 cells fivefold. Substances lowering the ATP level in the cells (oligomycin, etc.) increase the uptake of colchicine by L and L-53 cells by 2-4 times. Colchicine uptake by resistant cells is increased in the presence of these substances more than in sensitive L cells. Lumicolchicine, a structural analog of colchicine which does not bind with tubulin, the protein of the microtubules, stimulates colchicine uptake approximately equally by L and L-53 cells.