The influence of noise stress on plasma epinephrine and its binding to plasma protein in the rat.

The influence of a hypersonic noise stress on plasma epinephrine level and on the distribution of i.v. administered radioactive epinephrine between the free and the protein bound form was studied in the rat. The noise stress caused an elevation of epinephrine by 180%. The radioactive hormone was removed more slowly from the vascular compartment of the stressed animals, concomitantly the protein bound fraction increased.