Role of hyaluronan in regulating joint fluid flow

Hyaluronan, a glycosaminoglycan composed of alternating N-acetyl-D-glucosamine and D-glucuronate residues, linked β(1, 2, 3, 4) and β(1, 2, 3) respectively, was first isolated from synovial fluid by Karl Meyer [1]. It is present in concentrations between 2-4 mg/ml in human and rabbit synovial fluids and has an average molecular mass between 2000 (rabbit) and 7000 (man) kDa [2, 3, 4].