Related Experiment Video
Updated: Oct 1, 2026

An Ex vivo Culture System to Study Thyroid Development
Published on: June 6, 2014
Cyclic AMP level of human thyroid cells in monolayer culture. TSH induced refractoriness to TSH action
Abstract:
Thyroid cells from euthyroid patients with Graves' disease were cultured in a chemically defined medium. The cells preserved the ability to respond to TSH with 8-fold increase in cyclic AMP concentration. This cyclic AMP response to TSH was diminished by prior exposure of cells to TSH. The decrease in cyclic AMP response to TSH induced to TSH was reversible, was not associated with a similar decrease to cyclic AMP response to PGE1, and could not be attributed to increased phosphodiesterase activity or to decreased adenyl cyclase activity. The partial resistence to TSH stimulation of thyroid cells previously exposed to TSH may be due to changes in the TSH receptor, possibly caused by TSH itself.
Related Concept Videos
Intracellular Hormone Receptors
Target Cell Response to Hormones
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
Hyperthyroidism I: Introduction
Hyperthyroidism II: Pathophysiology
Graves Disease II: Pathophysiology
Hypothyroidism II: Pathophysiology

