HBS204 Lecture Notes - Lecture 8: Thyrotropin-Releasing Hormone, Anterior Pituitary, Thyrotropin Receptor
Document Summary
Hypersecretion causes - could be a tumour in the pituitary gland that autonomously secretes acth, acth targets the adrenal cortex to produce cortisol. If excess acth is secreted then there will be excess cortisol secreted, the tumour cells in the anterior pituitary are not regulated by negative feedback therefore uncontrolled secretion of acth from the anterior pituitary. It could be an adrenal tumour, a tumour in the adrenal gland itself that autonomously secretes cortisol. Individuals that had suffered from autoimmune destruction of the adrenal cortex, you could expect clinical tests to reveal high levels of circulating acth. Thyroxine - known as t4 and triiodothyronine - known as t3. It is known as t3 because it has three iodine atoms within the thyroid hormone, t4 has four iodine atoms within the thyroid hormone: t3 is the active hormone in target cells. Characteristics: new points to note - transport in the circulation thyroid hormone is bound to thyroxine-binding globulin and also albumins.
