Transcript hot level
BBio 351 – October 13, 2015 Outline for today: • Intro to endocrinology (continued) • Overview of hormones and their sources • 3 structural classes • Hormone distribution and activity • The hypothalamic-pituitary axis • Anatomy, including pituitary parts • Tropic hormones and feedback loops • End-of-chapter questions Sherwood Figure 7-1 3 structural classes of signal molecules: hormones Structure Synthesis Transport in blood Mechanism of action Examples Sherwood Table 7-1 Which hormones would you expect to have the slowest, longest-lasting effects? Why? Example of a prohormone: POMC arbl.cvmbs.colostate.edu/hbooks/pathphys/ endocrine/hypopit/acth.html How steroids are made Sherwood Figure 7-3 Hormone distribution & activity The hypothalamic-pituitary axis • Hormones often control the release of other hormones • Tropic hormones • Releasing Hormones • Inhibiting Hormones Anatomy: hypothalamus & pituitary Sherwood Figure 7-9 2 parts of the pituitary Hypothalamus-pituitary axis & negative feedback Martini (2015) Figure 18-8 (like Sherwood Figure 7-12) Hypothalamus-pituitary axis & negative feedback • Example: consider thyroid hormone as “Hormone 2.” Produced by Releasing Hormone: Hormone 1: Hormone 2: Thyroid Hormone Effects Nicknames for the pituitary? End-of-chapter questions (1) Would you expect the concentration of hypothalamic releasing and inhibiting hormones in a systemic venous blood sample to be higher, lower, or the same as the concentration of these hormones in a sample of hypothalamic-hypophyseal portal blood? Sherwood, page 334 End-of-chapter questions (2) Thinking about the feedback control loop among TRH, TSH, and thyroid hormone, would you expect the concentration of TSH to be normal, above normal, or below normal in an animal whose diet is deficient in iodine (an element essential for synthesizing thyroid hormone)? Sherwood, page 334 End-of-chapter questions (3) An animal displays symptoms of excess cortisol secretion. What factors could be measured in a blood sample to determine whether the condition is caused by a defect at the hypothalamic/anterior pituitary level or the adrenal cortex level? Sherwood, page 334 Diagnose the singing patient! What am I getting? I'm flushed and sweating, And I'm hot hot hot! (Hot hot hot!) My pulse is screaming; It's like I'm dreaming, But I'm not not not. (Not not not.) A bulging neck and bulging eyes -Yet my waist has shrunk in size. Tell me how, in middle age, Can I be low in TSH.... But hyperthermic? (Hyperthermic?) Feeling hot hot hot? (Hot hot hot?) Image by A.D.A.M.