Pituitary TSH cell

Pituitary TSH cell

Thyroid stimulating hormone (TSH)-producing cells or thyrotrophs form 5% of the anterior pituitary population. TSH consists of two subunits (α and β), which are located in separate genes on different chromosomes. The α-subunit is non-specific as it is also a component of other pituitary hormones (FSH, LH). The β-subunit is specific for TSH and gives the hormone its biological activity. After the synthesis of both subunits, they are glycosylated and transported through the Golgi-apparatus. When they are packaged into vesicles for secretion, the subunits combine to form the mature TSH.

TRH from the hypothalamus stimulates the transcription of TSH via a signal transduction pathway that is activated after binding to the TRH-receptor. The thyroid hormone is able to suppress the transcription of TSH via binding of the TH receptor (negative feedback). Similarly, TRH increases the rate of secretion of TSH, whereas TH decreases the release.