Some physiological factors affecting the binding of cortisol by human plasma proteins.
Steady-state gel filtration has been used to study the binding of cortisol to human plasma proteins in vitro. Raising the temperature from 37 degrees C to 41 degrees C results in the mean proportion of free (non-protein-bound) cortisol rising approximately from 7% to 11%. Addition of cortisol to plasma  identical to 275 nmol/l) also increased the proportion of free cortisol by approximately 50%. Cortisone is less strongly bound to plasma proteins than cortisol. The mean values (+/- S.D.) for five samples were free cortisol 8.4 +/- 1.1% and free cortisone 26.0 +/- 3.8%.
D001798:Blood Proteins / Q000378:metabolism*; D003348:Cortisone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood* / Q000302:isolation & purification; D007700:Kinetics; D008722:Methods; D011485:Protein Binding; D013696:Temperature
D001798:Blood Proteins; D003348:Cortisone; D006854:Hydrocortisone