title: The inhibitory effect of theophylline on the incorporation of 3H-deoxycytidine and 3H-thymidine into thymocyte DNA.
abstract: In short term cultures of rat thymic lymphocytes, theophylline caused an early inhibition of incorporation of 3-H deoxycytidine into DNA without influencing the incorporation of 3-H-thymidine. Over a 4-hr incubation period, the inhibitory effect of theophylline on 3-H-deoxycytidine uptake into DNA remained at approximately 40%, while the suppression of 3-H-thymidine uptake increased to 20%. The results indicate that since there is a difference in the effect of the ophylline on the incorporation of 3-H-deoxycytidine and 3-H-thymidine into the DNA of thymus lymphocytes, inhibition of uptake of these deoxynucleosides by theophylline does not necessarily reflect inhibition of DNA synthesis or cell turnover.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis*; D003841:Deoxycytidine / Q000378:metabolism*; D003864:Depression, Chemical; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D051381:Rats; D013806:Theophylline / Q000494:pharmacology*; D013936:Thymidine / Q000378:metabolism*; D013950:Thymus Gland / Q000378:metabolism*; D013997:Time Factors
chemical_list: D003841:Deoxycytidine; D004247:DNA; D013806:Theophylline; D013936:Thymidine