[Immunoreactive growth hormone in the urine of patients with acromegaly]

The use of an immunosorbent on the basis of monoclonal antibodies, electrophoresis in polyacrylamide gel and radioimmunoblotting has shown that immunoreactive growth hormone in acromegalic patients' urine is represented mainly by intact hormone with the molecular mass of 22 kD, large molecular products of its limited proteolytic splitting and, probably, by a small amount of an immunoreactive form, corresponding to hormone variant 20 K. The detection of the intact growth hormone in the urine confirms a possibility of characterization of hypophyseal somatotropic function by hormone excretion with urine, however taking into account the presence of immunoreactive products of its proteolysis in urine. A routine radioimmunoassay was shown unfit for the determination of growth hormone levels in urine. Specially adapted very sensitive methods are required for the purpose.