ADSC 4300 Lecture Notes - Lecture 16: Thyroid, Enzyme Inhibitor, Melatonin

• School: University of Georgia
• Department: Animal and Dairy Sciences
• Course: ADSC 4300
• Professor: Liu

Document Summary

Hormones are not only secreted by endocrine glands secrete hormones. Regulation of hormone signaling: hormones can have a biological action on the target cells. After target cells receive hormones, they can send signals back to modulate hormone secretion. This is known as feedback inhibition: two types negative & positive, outcome of negative feedback- stabilizes a system, example: thyroid gland is the target gland. It secretes t3 and t4 which will enter the blood and go to the pituitary to inhibit tsh secretion: outcome of p feedback- complete some type of function needed (not so common in the body) Pineal gland- melatonin: peak secretion ages 1-5 years old; by puberty is decreases. Hypothalamus & pituitary gland: endocrine is a controlling system, but this whole system is controlled by the hypothalamus & pituitary gland. Only 2 cells have inhibiting hormones: releasing hormones, gnrh, trh, crh, ghrh, prf.