PHGY 210 Lecture : PHGY 210 Lecture 2-Endocrinology.pdf
16 Mar 2012
School
Department
Course
Professor
Document Summary
The most common form of hormone release mechanism is negative feedback. Can feedback to one place, but sometimes get double feedback loop, where two things are inhibited. Calcium feedbacks to parathyroid gland, cortisol feedbacks to hypothalamus and anterior pituitary. Posterior pituitary gland secretes hormones that activate or inhibit the anterior pituitary gland. There is no direct link between the function of a hormone and its structure. Is an outgrowth of the hypothalamus, connected to it via pituitary stalk. Secretes oxitocin & vasopressin from 2 hypothalamic nuclei. Axon of both travel down to posterior pituitary. Prohormones of the two are processed in secratory granule (think vesicle) as they travel down the axon. Short half-life is metabolically expensive, but is good if want to fine tune. No known function in males, though secreted by posterior pituitary gland. Uterus highly sensitive to oxitocin and is a very powerful positive feedback mechanism to leads to uterus contraction.
