Related Experiment Video
Updated: Aug 6, 2026

Generation of a Mouse Spontaneous Autoimmune Thyroiditis Model
Published on: March 17, 2023
Exaggerated and prolonged thyrotrophin releasing hormone (TRH) test responses in tertiary hypothyroidism
Abstract:
A 60 year old man with panhypopituitarism due to a large meningioma and prolonged and exaggerated thyroid stimulating hormone (TSH) responses is described. Initial investigations showed a subnormal urinary free cortisol concentration, a low serum cortisol taken at 0900 hours, and a low free T4 concentration. The TSH was towards the upper end of the normal range. Subsequently pituitary function tests showed subnormal production of luteinising hormone in response to luteinising hormone releasing hormone (LHRH) and a short synacthen test with a low 30 minute cortisol value. Long synacthen testing showed a normal response at four days, confirming that the abnormalities were due to a pituitary or hypothalamic cause. A computed tomogram showed a large meningioma compressing the hypothalamus, pituitary, and temporal lobe. TRH testing showed a prolonged and exaggerated response, consistent with tertiary hypothyroidism.
Related Concept Videos
Synthesis and Regulation of Thyroid Hormones
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
Functions of Thyroid Hormones
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
Hyperthyroidism I: Introduction
Hyperthyroidism II: Pathophysiology
Graves Disease II: Pathophysiology
Hypothyroidism II: Pathophysiology
