An in vitro study of the effects of lead on an epithelioid cell line.

The effects of a growth-inhibiting dose of lead on the cell surface, mitochondria, and vacuoles of RLC-GAI cells, an epithelioid cell line, were examined. The cells were found to begin to retract from the culture dish, becoming rounded in shape as early as 6 hours after lead addition. The rounded cells were found to be more susceptible to osmotic shock than normal cells. Studies with cytochalasin B showed that microfilaments were able to polymerize in the lead-treated rounded cells and microvilli were normal. Calcium did not prevent cell rounding by lead. Lead-induced detachment was reversed when cells were placed in normal medium. Mitochondrial and vacuolar alterations became apparent after several additional days. There was a decrease in the fraction of cytoplasm containing mitochondria and in the amount of cristae surface area in mitochondria. In cells incubated in mainly particulate lead increased numbers of lead-containing vacuoles were also seen.