DNA degradation in the kidney of folic acid-treated guinea pigs.

Previous investigators agree on the increased DNA synthesis and destruction of tissues caused by folic acid (FA) administered parenterally. This study aims to clarify whether DNA degradation due to the destruction of cells and nuclei precedes DNA synthesis following FA administration. Forty guinea pigs were divided into four groups: group 1, contained 10 controls; in group 2, ten animals received intraperitoneally 300 mg/kg of body wt FA; in group 3, ten animals received FA and 12 h later frusemide intramuscularly in a dose of 7 mg/kg body wt; and finally in group 4, ten animals received frusemide as in group 3. FA produced necrosis of the epithelial cells of the convoluted tubules as the detection of the beta-aminoisobutyric acid end product of DNA and thymine catabolism indicated. Frusemide administered in group 3 had a favourable effect on the acute renal failure induced by FA.