PARADOXICAL RESPONSIVENESS OF ADRENOCORTICOTROPIN AND CORTISOL TO THYROTROPIN RELEASING HORMONE (TRH) IN PREGNANT WOMEN. EVIDENCE FOR INTERMEDIATE LOBE ACTIVITY?

Abstract

In 7 pregnant women, plasma immunoreactive ACTH and cortisol rose paradoxically after intravenous administration of TRH but not after saline. This anomalous response to TRH is reminiscent of that in about one third of patients with Cushing's disease. These observations adduce inferential evidence to the concept that in pregnancy and in a subgroup of patients with Cushing's disease the intermediate lobe of the pituitary is the source of circulating immunoreactive and bioactive ACTH responding to TRH.