title: Repair and de novo replication of rat lung DNA following instillation of 3-methylcholanthrene.
abstract: Structural analysis of rat lung DNA was made by stepwise elution of the nucleic acid from benzoylated--DEAE-cellulose with 1.0 M NaCl and 30% formamide solutions respectively, the DNA content of collected fractions being determined by absorbance. The proportion of the minor fraction, which was eluted with formamide and thought to contain DNA having single-stranded regions, was increased by intratracheal instillation of 3-methylcholanthrene prior to death of the animal. Maximum initial increase was observed 14 h after treatment. Analysed up to 10 days after treatment, there was a biphasic response, the early maxima being dose dependent and the second apparently independent of the amount of hydrocarbon administered. The data implicate DNA repair processes and cellular proliferation stimulated by 3-methylcholanthrene as being involved in recovery of the lung from this potentially carcinogenic insult.
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004260:DNA Repair / Q000187:drug effects*; D004261:DNA Replication / Q000187:drug effects*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism; D008748:Methylcholanthrene / Q000633:toxicity*; D051381:Rats; D013997:Time Factors
chemical_list: D008748:Methylcholanthrene