Effects of ZnCl₂ on MTT reducing activity in different cell lines.

<p>Cells were exposed to ZnCl_<b>2</b> at 0.1 or 1 mM in either the presence or absence of CaCl_<b>2</b> and EGTA for 1 h, followed by culture for an additional 24 h and subsequent determination of MTT reducing activity. Values are the mean±S.E. of percentages over the maximal activity detected in cells not exposed to any test chemicals in 3 different experiments. *P<0.05, **P<0.01, significantly different from the control value in cells not exposed to ZnCl₂. ^#P<0.05, ^#P<0.01, significantly different from the value in cells exposed to ZnCL₂ at each concentration.