title: [Cellular test for RNA-synthesis in rat bone marrow and its use in testing cryoprotective and toxic agents].
abstract: A system for the measurement of the RNA-synthesis of bone marrow cells of the rat has been developed and the incorporation of [3H]-uridine into the cellular RNA has been standardized with respect to the time of incubation, the concentration of [3H]-uridine and the number of cells. A plateau of the incorporation of [3H]-uridine into the RNA is reached after 20 min of incubation and is interpreted as the expression of a steady state in synthesis and degradation of the cellular RNA. A constant labelling of the RNA is reached above 8.3 with 10(-6)M [3H]-uridine. The optimal cell number in the 500 mul standard assay is 4 with 10(6). Actinomycin D inhibits the RNA-synthesis to 94% in a concentration of 1.2 with 10(2) mug/ml. The cryoprotectants dimethylsulfoxide, polyethylene-oxide and glycerol and the potential haematotoxic substances dichlorodiphenyltrichloroethane and gamma-hexane were tested in this system. 5% dimethylsulfoxide and 10% polyethylen-oxide in Eagle's-medium with ethylendiamintetra-acetate do not influence the RNA-synthesis. 5% glycerol reduces the incorporation of [3H]-uridine into the cellular RNA to about 30%.
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000378:metabolism*; D001854:Bone Marrow Cells; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D006843:Hydrocarbons, Chlorinated / Q000494:pharmacology*; D011095:Polyethylenes / Q000494:pharmacology; D012313:RNA / Q000096:biosynthesis*; D051381:Rats; D014240:Trichloroethanes / Q000494:pharmacology*
chemical_list: D003451:Cryoprotective Agents; D006843:Hydrocarbons, Chlorinated; D011095:Polyethylenes; D014240:Trichloroethanes; D012313:RNA; D004121:Dimethyl Sulfoxide
vernacular_title: Ein zellulärer RNS-Synthese-Test mit Rattenknochenmark und seine Anwendung bei der Testung von Kryoprotektiva und zur Erfassung von Schadstoffen