ANAT 322 Lecture Notes - Lecture 8: Janus Kinase 2, Stat5, Cell Adhesion

• School: McGill University
• Department: Anatomy & Cell Biology
• Course: ANAT 322
• Professor: David Ragsdale

Document Summary

Hormone (secreted by endocrine gland & circulates in blood) and local growth factor (paracrine/autocrine) Lactotrophs 20-50% of ap weight, depending on physiological state (lactation vs normal) Prolactinoma: cancer of ap, originate from lactotrophs, secrete high amounts of prolactin. But if remove ap, still 20% prolactin in serum other sources of prolactin in body. Regulation of prolactin synthesis from extrapituitary prolactin is completely diff from regulation in pituitary. Hypothalamus artery capillary bed of median eminence (base of hypothalamus) portal veins capillary bed of anterior pituitary vein whole body. Median eminence concentrates neuropeptides secreted by hypothalamus, even if low concentrations. Need high concentrations for effect on pituitary cells; otherwise diluted. Hypothalamus inhibits prolactin secretion (when normal connection w/ap) Remove pituitary, implant over kidney capsule high prolactin secretion. Cut stalk b/w hypothalamus & ap high prolactin secretion. 3 dopaminergic neurons originating from hypothalamus that inhibit prolactin secretion in ap. Tida neurons end in me, secrete dopamine into me portal vein prolactin release.