Wednesday, 21 September Chapter 11 The Endocrine System Chapter 6 Nervous System A and B Two 1QQs returned on Piano Lab this week: Analyzing a research paper + First Endocrine Case study. Lab next week: Four more cases in endocrinology

1QQ # for 8:30 1) Suppose the portal vessel that connects the median eminence to the adenohypophysis was completely occluded (blocked.) Which hypothalamic hormone(s) could not reach their target cells? a) ACTH b) CRH c) DA d) Prolactin e) TRH f) TSH g) FHS h) T3 i) GnRH j) ADH OR 2A Name the hormone normally secreted by hepatocytes. 2B Name the hormone secreted by cells in the adenohypophysis that stimulates the secretion of the “liver” hormone. 2C Suppose liver cells form a tumor that secretes the “liver” hormone in an unregulated manner. Assuming cells in the adenohypophysis are behaving normally, would the levels of the tropic hormone from the anterior pituitary be normal, high, or low? Write the number of the one question you choose to answer.

1QQ # for 9:30 1) Suppose the portal vessel that connects the median eminence to the adenohypophysis was completely occluded (blocked.) Which hypothalamic hormone(s) could not reach their target cells? a) Oxytocin b) Prolactin c) DA d) CRH e) TRH f) TSH g) FHS h) T3 i) GnRH j) ADH OR 2 Cells in the anterior pituitary gland that secrete TSH a) have receptors for TRH in their cell membranes b) can sense the levels of T3 and T4 in the plasma c) will release more TSH as levels of TRH rise d) Should release less TSH after a person has been treated with radioactive iodine e) Should release less TSH if a person is dosed with exogenous TH. Write the number of the one question you choose to answer.

Tropic hormones control the function Trophic hormones promote survival and growth of targets Releasing HormoneRelease-inhibiting Hormone Hypothalamo-hypophyseal portal system A A S S P P PPP PP PPPP S 6

Tropic hormones control the function Trophic hormones promote survival and growth of targets Releasing Hormone Release Inhibiting Hormone Long-loop negative feedback Short-loop Neg. Feed. S 7

⇧Cortisol secretion from Adrenal Cortex Mobilize fuel from muscle & adipose tissue Suppress non-essential functions (reproduction & growth) Suppress inflammatory & immune responses Potentiates response to EPI (vascular smooth muscle) ACTH from Ant. Pit CRH from Hypothalamus Physical trauma Prolonged exposure to cold Prolonged intense exercise Infection Sleep deprivation Pain Fright Emotional distress Vasopressin Cytokines from immune cells Excess Cortisol from 1) adrenal cortex tumor (primary) or 2) hypersecretion of ACTH from anterior pituitary (secondary) Cushing’s Syndrome Basal levels of Cortisol Required for normal sensitivity to EPI; symptoms of excess cortisol are….. Clinical example: treatment of chronic inflammation (e.g. arthritis) with high doses of cortisol can lead to Cushing’s Syndrome! S 8

Who Cares?

⇧Cortisol secretion from Adrenal Cortex Mobilize fuel from muscle & adipose tissue Suppress non-essential functions (reproduction & growth) Suppress inflammatory & immune responses Potentiates response to EPI (vascular smooth muscle) ACTH from Ant. Pit CRH from Hypothalamus Physical trauma Prolonged exposure to cold Prolonged intense exercise Infection Sleep deprivation Pain Fright Emotional distress Vasopressin Cytokines from immune cells S 8

Age 16, 33, 52 No Relation! S 4

Disorder =Acromegaly Type of endocrine disorder = ???? Excessive growth of bones and soft tissues of face and hands, and feet. Hypersecretion of Growth Hormone from adenohypophysis or ectopic tumor in adults Treatment? Somatostatin analogs? GH receptor blockers Transphenoidal resection/ablation with focal radiation Compare to Pituitary Gigantism S 5 GHRH SS GH

Applied Physiology: Menopause Widmaier text p Onset ~ age 50 Irregular menstrual cycles Breasts and genital organs gradually atrophy Decrease in bone mass & strength (osteoporosis) (bone resorption > bone deposition) Hot flashes…sweating, etiology unknown Increased incidence of coronary artery disease S 9

Menopause, continued. Caused by ovarian failure….loss of estrogen Estrogen has protective function for cardiovascular system and sustains bone Diagnosis –Test estrogen levels –Test FSH levels….interpretation if high? Treatment –Hormone replacement therapy –Risk of HRT: increased incidence of breast cancer & uterine endometrial cancer –Advantages: alleviates symptoms, restores cardiovascular protection, sustains bone density S 10

Neurons? Endocrine cells? Neuroendocrine cells? S 6 Neurons and endocrine cells are very involved in homeostasis. To Chapter 6!