Acid a1-glycoprotein in serum
Apr 24, 2018
Reference values for the concentration of acid a1-glycoprotein in serum are 13.4-34.1 μmol / l( 0.55-1.4 g / l).
Acid a1-glycoprotein( orosomukoid ) is a protein of the blood plasma, the richest in carbohydrates. The carbohydrate moiety is represented by several polysaccharide chains attached to the polypeptide chain. It has the ability to inhibit the activity of proteolytic enzymes, alter the adhesion of platelets, suppress immunoreactivity, bind many drugs( propranolol) and some hormones( progesterone).
Orosomucoid belongs to the acute phase proteins. Its synthesis is stimulated by lipopolysaccharides released from macrophages activated by interleukin-6( IL-6).The content of orosomukoid in the blood increases with inflammatory processes( infections, rheumatic diseases, trauma, surgical interventions), tumors. The study of this indicator in dynamics allows to evaluate the dynamics of the inflammatory process, and in tumors, in case of their operative treatment, to diagnose the occurrence of relapse.
Because the concentration of orosomucoids in the blood increases in inflammatory processes, it is able to bind an increased amount of drugs that the patient receives, so that
dissociation can occur between the pharmacological effect and the concentration of the drug in the blood.
A reduced concentration of orosomukoid in the blood serum is possible in early childhood, during pregnancy( at early stages), severe liver damage, nephrotic syndrome, estrogen administration, oral contraceptives. With age, the concentration in the blood of albumins and especially of the a1-glycoprotein decreases;since many drugs( such as lidocaine, propranolol, tricyclic antidepressants) are associated with these proteins after they enter the bloodstream, it is possible for the elderly to increase the content of their free fraction, which creates prerequisites for enhancing pharmacodynamic action and the occurrence of side effects.
The joint determination of orosomucoid and haptoglobin in serum is important for the diagnosis of hemolysis in vivo. Usually, the concentrations of these two proteins in acute phase processes increase and decrease simultaneously, an increased content of orosomukoid with a normal content of haptoglobin indicates the flow of an acute phase process with moderate hemolysis in vivo.