Rachow J W, Ryan L M
Arthritis Rheum. 1985 Dec;28(12):1377-83. doi: 10.1002/art.1780281210.
Synovial fluid adenosine triphosphate pyrophosphohydrolase, an enzyme which manifests increased activity in chondrocalcinosis and osteoarthritis, was partially characterized in synovial fluids from 41 patients who had a variety of arthropathies. Activity was found to be a soluble, heat labile, and divalent cation-dependent nonspecific nucleotide pyrophosphohydrolase with pH optimum 9.0-9.5.