An adenohypophysis hormone which is regulated by the feedback mechanism is
TSH
Thyroid-stimulating hormone (TSH) is secreted by the adenohypophysis. It controls the secretion of thyroid hormones by the thyroid gland.
To maintain the levels of thyroxine in blood under normal, the secreted thyroxine shows a negative effect of the adenohypophysis which inhibits the secretion of TSH.