Plasma Proteins
Plasma contains a number of important proteins. These proteins are typically synthesised in the liver, the exception being immunoglobulins (γ globulins or antibodies) which are synthesised by lymphocytes (mainly B-cells or plasma cells).
There are 3 main classes of plasma protein:
The typical distribution of plasma proteins is shown in the table below:
Buffers
Plasma proteins have the ability to accept or donate H+ ions, which means they can cat as buffers and become cations (positively charged) or anions (negatively charged).
This ability to accept and donate hydrogen ions is due to the presence of amino (NH2) and carboxyl (COOH) groups.
At normal pH most plasma proteins are in their anionic form.
There are 3 main classes of plasma protein:
- Albumin
- Fibrinogen
- Globulins (which are subdivided into α, β, and γ globulins)
The normal plasma protein concentration is 60-80 g/L
The normal albumin concentration is 35-50 g/L
The normal albumin concentration is 35-50 g/L
The typical distribution of plasma proteins is shown in the table below:
| Protein | Concentration (g/L) | Function |
|---|---|---|
| Albumin | 35-50 | Oncotic pressure Drug and hormone binding |
| α globulins | 5.5 | Copper transport antiproteases |
β globulins
| 3 1 0.7 1.6 | Iron tansport Blood clotting Blood clotting Immune response |
| Fibrinogen | 3 | Blood clotting |
| γ globulins | 13 | Immune response |
Buffers
Plasma proteins have the ability to accept or donate H+ ions, which means they can cat as buffers and become cations (positively charged) or anions (negatively charged).
This ability to accept and donate hydrogen ions is due to the presence of amino (NH2) and carboxyl (COOH) groups.
At normal pH most plasma proteins are in their anionic form.