To Estimate the Amount of Total Protein and Albumin in Serum and to Find A/G Ratio
Proteins are present in all body fluids but show very high concentration (> 3 g/dl) in plasma, lymphatic fluids, and some exudates. The amount of total proteins in serum decreases in the third trimester of pregnancy. The measurement of total proteins in serum is useful to assess the conditions related to changes in plasma or fluid volumes, such as shock and dehydration. A total serum protein test measures the total amount of proteins in the blood. Serum proteins mainly consist of albumin but few globulins (such as α1-globulin) also may be measured. Fibrinogen is the protein present in plasma but not in serum. Albumin is a major constituent of human plasma and represents about 40–60% of total proteins. Albumin is involved in transport and storage of wide variety of ligands and maintaining the osmotic pressure of plasma. It also serves as a source of endogenous amino acids. Albumin is mainly measured to check liver and kidney functions but is also important in determining the cause of swelling of the ankles (edema) or abdomen (ascites).