Cytotoxic effects of four antibiotics on endothelial cells

Intravenous administration of antibiotics often causes local pain and thrombophlebitis at the site of injection. An in vitro model that could predict these effects would be of great value. In this study the effects of four antibiotics, benzylpenicillin, cefuroxime, dicloxacillin and erythromycin, have been evaluated on three types of endothelial cells in culture. The cell types employed were primary culture from human umbilical vein, primary culture from bovine aorta, and the cell line EA-hy 926, a hybride endothelial cell. These cells were exposed to antibiotics for 24 hr and subsequently toxic effects on cells were evaluated by three different assays. Benzylpenicillin was atoxic in all types of cells and in all assays, in contrast to the other antibiotics. The other three antibiotics exerted dose dependent toxic effects in all investigated cells when DNA-synthesis and total cell protein were used as toxicity assays but the results varied between the cell types. There were no significant differences between the effects of cefuroxime, dicloxacillin and erythromycin on bovine endothelial cells. In the other cell types, however, there were significant differences between some drugs but the outcome depended on the cell type. It is concluded that it is possible to show differences between the effect of antibiotics on endothelial cells, but the result depends on the cell type employed.