MSH: A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.,CSP: poly(glucosamine sulfate-glucuronic acid); endogenous mucopolysaccharide with antithrombin and lipotropic activities; USP injection is used as an anticoagulant.,SPN: Enzyme preparations are products that are used in the histopathology laboratory for the following purposes: (1) To disaggregate tissues and cells already in established cultures for preparation into subsequent cultures (e.g., trypsin); (2) To disaggregate fluid specimens for cytological examination (e.g., papain for gastric lavage or trypsin for sputum liquefaction); (3) To aid in the selective staining of tissue specimens (e.g., diastase for glycog