Table 2.

Protein thiols, protein disulfides and GSH determined in OVCAR-3 cells. The data are presented as the means ± S.D. of three independent determinations of the same sample.

Thiols
Cell lysate pellet suspension	Protein thiols (P-SH)a	GSH (nmol/million cells)
Before NaBH4 reduction	30.96±0.23	Not detected
After NaBH4 reduction	33.69±1.43	Not detected
Disulfides
Protein disulfidesb	Protein disulfides derived from mixed disulfides with GSHc
1.37±0.83	Not detected

^aexpressed as GSH equivalents, nmol/million cells

^b $\text{Protein}\text{disulfides}=\frac{(\text{P}-\text{SH}\text{after}{\text{NaBH}}_4\text{reduction}-\text{P}-\text{SH}\text{before}{\text{NaBH}}_4\text{reduction})}{2}$; (expressed as GSSG equivalents, nmol/million cells)

^c $\text{Protein}\text{disulfides}\text{derived}\text{from}\text{mixed}\text{disulfides}\text{with}\text{GSH}=\frac{(\text{GSH}\text{after}{\text{NaBH}}_4\text{reduction}-\text{GSH}\text{before}{\text{NaBH}}_4\text{reduction})}{2}$; (expressed as GSSG equivalents, nmol/million cells)