[The effect of so-called basic therapeutics and symptomatically effective antirheumatic drugs on the enzymes of DNA synthesis and DNA repair].

Investigation of DNA-synthesis and DNA-repair are important for evaluating mutagenic effects of drugs. Among the tested non steroidal antirheumatic drugs metiacinic acid, ketoprofene, and azapropazone do not show any effect on these mechanisms. Tolmetin and indometacine, however, inhibit DNA-synthesis only, whereas naproxene, oxyphenylbutazone, and flufenamic acid inhibit both DNA synthesis and repair. Gold does not influence DNA synthesis or repair, D-penicillamine inhibits DNA-synthesis only. However, Chloroquine and metabolised cyclophosphamide respecitvely impair both DNA-synthesis and repair. This effect may be also caused by azathioprine in high dosage. Application of two repair- inhibitors or of one DNA-repair-inhibitor and one directly mutagenic acting drug, e.g. cyclophosphamide, should therefore be avoided.