An improved method of determination of SH group concentration and reactivity in plasma of patients with various clinical disorders and in rats after administration of indomethacin or carbon tetrachloride.

Plasma SH group concentration and reactivity were determined in man and rat in the sulfhydryl-disulfide exchange reaction with 5-5' dithiobis (2 nitrobenzoic acid) (DTNB). Both parameters were assayed in the same sample using different DTNB concentrations: 1 mM and 0.05 mM DTNB were employed in human and rat plasma, respectively. The method was applied to patients with liver diseases and rheumatoid arthritis with and without treatment with antiinflammatory drugs and to rats after administration of indomethacin or carbon tetrachloride.