Increased copper ligand reactivity in the urine of patients with rheumatoid arthritis

✍ Scribed by Donald A. Gerber

• Publisher: John Wiley and Sons
• Year: 1966
• Tongue: English
• Weight: 570 KB
• Volume: 9
• Category: Article
• ISSN: 0004-3591
• DOI: 10.1002/art.1780090607

✦ Synopsis

By DONALD A. GERBER umIc ION^ and drugs modifying the C course of rheumatoid arthritW4 have been shown to have in common the ability to alter sulfhydryl group reactivity.

The following studies were performed to determine whether patients with rheumatoid arthritis excrete in their urine increased amounts of substances that alter the reactivity of cupric ion.

Methods

Biscyclohexanoneoxaldihydrazone (cuprizone)' reacts with the cupric ion to give a clear, stable, blue-colored solution with a constant absorbance over a pH range of 7.0 to 9.0. Cuprizone does not give a color with any other cations or anions commonly encountered in biological materials.5 The extent to which an aliquot of urine can suppress this color formation has been used as a measure of the concentration of copper ligand reactivity in urine. A copper ligand in this sense is defined as a substance which binds to copper. In the method devised, three stock solutions were prepared. Solution A: 0.5 ml. 0.02 M CuSO, + 295 ml. 0.1 M phosphate buffer (pH 7.4) + 4.7 ml. 1.0 M sodium citrate. Solution B: 10 m q cuprizoue