Table 1. Effect of glutathione depletion on Glutathione S-Transferase (GST) activity.

Time of culture	Category	GST mU/mg prot.	SD
24 h	control	0,313	0,057
24 h	DEM	0,473	0,077
24 h	BSO	0,398	0,074
6 days	control	0,656	0,047
6 days	DEM	0,715	0,034
6 days	BSO	0,533	0,256

The 3T3 fibroblasts were treated with 100 µM diethylmaleate (DEM) or with 10 µM buthionine sulfoximine (BSO) immediately after attaching. The activity of the GST was determined at 24 h and 6 days of culture, as described in Materials and methods.