title: [Mouse cell accumulation of Colcemid and colchicine in tissue culture].
abstract: Kinetics of the uptake of 3H-colchicine and 3H-colcemid by mouse transformed L cells has been studied. The amounts of colchicine and of colcemid, accumulated by cells during a long-term incubation appeared to be equal; however, the initial uptake rates being higher for colcemid. The rates of the efflux of 3H-colchicine and 3H-colcemid were also different. After a 3 hours incubation of cells in antitubulin-free medium, the cells retain as much as 70% of colchicine, and only 10% of colcemid. It is known that colchicine does not bind tubulin at 0 degrees C; a colchicine analog lumicolchicine does not bind tubulin at any temperature. We have shown that the rate of 3H-lumicolchicine efflux at 37 degrees C is very rapid. The same was true for colchicine, if the incubation with the drug was performed at 0 degrees. We suggest that the difference in the rates of influx and efflux between colchicine and colcemid may be due to differences in their capacities of binding tubulin and dissociating from it.
mesh_terms: D000818:Animals; D003078:Colchicine / Q000378:metabolism*; D046508:Culture Techniques; D003703:Demecolcine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007700:Kinetics; D007739:L Cells / Q000378:metabolism*; D051379:Mice; D013997:Time Factors; D014316:Tritium
chemical_list: D014316:Tritium; D003078:Colchicine; D003703:Demecolcine
vernacular_title: Nakoplenie koltsemida i kolkhitsina myshinymi kletkami v kul'ture tkani.