Plasma Proteins

• Plasma proteins are proteins present in the blood plasma and are produced by the liver (except for immunoglobulins)
• Plasma proteins are produced by the rough ER in hepatocytes and exported into the blood via the Golgi complex
• There are a number of different types of plasma proteins, each serving different specific functions
• Albumins regulate the osmotic pressure of the blood (and hence moderate the osmotic pressure of body fluids)
• Globulins participate in the immune system (i.e. immunoglobulins) and also act as transport proteins
• Fibrinogens are involved in the clotting process (soluble fibrinogen can form an insoluble fibrin clot)
• Low levels of other plasma proteins have various functions
• Protein breakdown: Albumin (60%), Globulins (35%), Fibrinogens (4%), Other (<1%)