稳定性/保质期:
Analysis Note: Protein determined by biuret.
Ceruloplasmin (Cp), the primary carrier of copper in plasma, is believed to play a role in oxidative modification of lipoproteins and participate in the acute phase response during stress. Cp acts as an effective antioxidant against various radicals and possesses potent peroxidase activity that decomposes hydrogen peroxide in the presence of reduced glutathione. It inhibits myeloperoxidase's peroxidase activity in a concentration-dependent manner and selectively binds to it in vitro, suggesting its role in the clearance and inactivation of myeloperoxidase in vivo.
At physiological (micromolar) concentrations, Cp was found to inhibit relaxation of rabbit aorta induced by endothelium-dependent agonists such as acetylcholine or ADP. However, it was ineffective in causing vasodilation due to direct stimulation of smooth muscle cells by nitroglycerin.
Unit Definition: One unit will cause a ΔA550 of 0.01 per minute using N,N-dimethyl-p-phenylenediamine as the substrate at pH 5.5 and 37°C, in a 7 mL reaction volume.
Physical Form: Pale blue powder containing sodium chloride and sodium acetate.