Effects of zirconium and aluminum salts on the alveolar macrophages

Alveolar macrophages from the rabbit were exposed in the culture medium to zirconium and aluminum salts. The specific activities of the lysosomal hydrolases, that is acid phosphatase, beta-N-acetylglucosaminidase and beta-glucuronidase, were measured in the medium, whole cell homogenate, mitochondrial fraction, and in the supernatant fraction. A highly significant increase of these hydrolases was observed in the mitochondrial fraction from cells exposed to zirconium and aluminum salts as compared with those from control cell cultures. However, release of these enzymes into the medium was not much. The phenomenon of macrophage phagocytosis was observed morphologically in the cell cultures exposed in vitro to these metal compounds.