Measurement of the production rate of human luteinizing hormone using the urinary excretion technique.

Labeled and/or unlabeled human luteinizing hormone (hLH) was injected into normal and abnormal males and into hypopituitary patients. In two patients, two phases of disappearance (T 1/2) were found to be 1.2 and 2.4 hr. Labeled and unlabeled hormone were excreted in the same proportion. Of the injected hormone, normal males excreted 10.1% plus or minus 0.9%, hypopituitary patients excreted 11.4%- 17.5% and two other patients excreted 10.3% and 5.3% over 48 hr. The urinary excretion of unlabeled hLH in normal males was 22.1 plus or minus 4.9 IU/24 hr. The production rate of hLH in normal males was 224.3 plus or minus 65.3 IU/24 hr and, in the two abnormal males, was five times higher. The advantages of this methodology are discussed.