Effect of bromocarbamide on fibroblasts in vitro: fine structural changes in mouse fibroblasts.

Summary As part of our research series with bromocarbamide, we examined the ultrastructural effect of bromocarbamide on cultured fibroblasts. Monolayers of the cells were grown on millipore filters in the presence of dissolved bromocarbamide and the filters were embedded in capsules so that longitudinal cross-sections of the cells could be observed. Electron microscopically, we observed increased numbers of microvilli and increased pseudopodia at the external cell surface, increased pinocytotic activity (examined with exogenous peroxidase), increased lipid droplet aggregation in the cytoplasm and increased cellular overlap. Two possibilities are proposed to explain these phenomena: one involving direct attack of bromocarbamide on the plasma membrane, and the other, a direct interference with cellular metabolism.