PubMed · 1973 · 145 citations · 0 references
Life SciencesBiochemistryMolecular BiologyDna RepairHepatotoxicologyNucleic Acid BiochemistryDna DamageDna Strand BreaksLiver RegenerationSingle-strand Break RepairDna Damage InductionDna Repair KineticsDna Single-strand BreaksDna Strand Break AnalysisDna Strand Break RepairHydroxyapatiteLiver Regeneration After Partial HepatectomySingle-strand Dna Breaks
Summary Alkaline sucrose gradients were used to study the induction of single-strand breaks in and repair of rat liver DNA in vivo. Liver DNA was labeled during regeneration after partial hepatectomy. DNA was isolated from the organ in such a way as to minimize the induction of breaks due to handling or enzymatic activity. Different methods of preparing high-molecular-weight liver DNA were compared. Best results were obtained by squashing the liver in an ethylenediaminetetraacetic acid-sodium chloride buffer. Using this squash technique and alkaline sucrose gradients, high-molecular-weight DNA was regularly obtained. This DNA behaved like single-stranded DNA on hydroxyapatite columns and contained no detectable contamination of protein or RNA. It was demonstrated by the method described that hepatic DNA damage was produced within four hr by the administration of methyl methanesulfonate and that the rat can repair such hepatic DNA damage in vivo within 48 hr.