1. Endocrine System for copying

2. Endocrine vs nervous system act together to coordinate body’s activities both: – use chemical messengers to communicate cell to cell – major function: homeostasis endocrine: slower response time – hormones transported thru circulatory system – target cells (any cell with hormone receptor) anywhere in body nervous: quicker conduction of signals – neurotransmitters – act on cells close by

3. Glands EndocrineExocrine no ducts secretions released and diffuse into blood capillaries have ducts secretions released onto surface example: sweat glands, salivary glands

4. 2 types of hormones PeptideSteroid bind to protein receptors in cell membranes (do not enter cell) receptor-hormone activate enzyme in cytoplasm  series of reactions result in cell response enter cell & bind to receptor in cytoplasm or nucleus Activates transcription of gene  protein produced generally action slower than peptide hormone

5. Endocrine system

6. hypothalamus part of brain secretes “releasing” hormones that act on pituitary gland axons that store the 2 posterior pituitary hormones end there

8. Pituitary gland 2 lobes: posterior & anterior

9. Negative Feedback Inhibition

10. Thyroid Gland stimulated by TSH secretes thyroxin (T4) and triiodothyronine (T3) – (-) feedback inhibition both have similar effects on target cells

11. hypothyroidism Thyroid produces too little hormone several causes: Hashimoto’s autoimmune/ lack of Iodine in diet  goiter (enlargement of thyroid due to increased TSH stimulation Symptoms: – Adults: lethargy, weight gain, anovulatory cycles – Infants:cretinism: dwarfism, low IQ, failure to reach sexual maturity

12. hyperthyroidism excessive secretion of thyroid hormones

13. Parathyroid Glands 4 small glands embedded in posterior surface of thyroid gland secrete: parathyroid hormone (PTH) – regulated by serum Ca++ levels actions: 1.stimulates removal of Ca++ from bone 2.increases kidney tubules reabsorption of Ca++ 3.activates vit D which enhances Ca++ absorption from food

14. thymus upper thorax, posterior to sternum largest in infants, decreases as we age produces: thymosin – programs T cells

15. Adrenal Cortex outer layer produces 2 kinds of steroid hormones 1.Glucocorticoids – major 1 – cortisol: – reduces swelling by inhibiting immune system/ raises serum glucose (stimulates liver to make glucose from proteins or lipids 2.Mineralocorticoids – major 1- aldosterone – acts on kidney to promote absorption of Na+ & excretion of K+

16. pancreas 1.Insulin – protein – reduces blood glucose by increasing entry of glucose into cells/making glycogen in hepatocytes – regulated by blood glucose levels 2.Glucagon – protein – raises blood glucose by acting on glycogen stores in liver – regulated by blood glucose levels

17. testes paired oval organs suspended in scrotum site of: – spermatogenesis – production of androgens: 1.Testosterone major one – made by interstitial cells/stimulated by FSH & LH – produces male 2 ◦ sex characteristics in puberty – promotes growth & maturation of reproductive system organs – increases libido

18. ovaries paired, almond-shaped organs in pelvic cavity produce ova release: estrogens & progesterone begin functioning in puberty in response to anterior pituitary gonadotrophins

19. estrogens Estrone &Estradiol made by follicle where ova is maturing stimulate: – development of 2◦ sex characteristics work with progesterone to prepare uterine lining for implantation help maintain pregnancy & prepare breasts to lactate(those estrogens made in placenta)

20. progesterone made &secreted by corpus luteum acts with estrogen to prepare uterine lining for implantation quiets uterine muscle during early pregnancy helps prepare breasts for lactation

21. placenta produces hCG (human Chorionic Gonadotropin) – stimulates corpus luteum of ovary to continue producing estrogens and progesterone so lining of uterus does not slough off (like in menstruation) – turns pregnancy tests + – by 3 rd mo pregnancy placenta produces estrogen & progesterone (ovaries become inactive rest of pregnancy) – also produces hPL (human placental lactogen) works w/E & P in preparing breasts for lactation

22. Pituitary disorders Anterior Pituitary Posterior Pituitary Giantism : hypersecretion hCG during chidhood abnl increse in length of long bones hypersecretion hCG in adulthood  acromegaly (epiphyseal plates sealed) see thickening of bones of hands, face & thickening of skin on brow Diabetes Insipidus: defects in ADH excrete large volumes of urine  dehydration & thirst (bed-wetting in children) can die w/in 2 days from the dehydration

23. Thyroid gland disorders Hypothyroidism: Cretinism: congenital hypothyroidism – severe mental retardation if not tx’d – most states require testing new borns Myxedema:adults – hallmark:edema of facial tissues, slow HR, low body temp, sensitivity to cold, dry skin & hair, muscle weakness

24. Thyroid gland disorders Graves Disease most common form of hypothyroidism 7 – 10 x more common in females autoimmune disorder: autoantibodies that mimic TSH  causes thyroid to grow & make thyroid hormones signs: enlarged thyroid, exophthalmos tx: surgical excision of all or part of thyroid or use of antithyroid drugs to block synthesis of hormones

25. goiter enlarged thyroid could be associated with hypo- or hyperthyroidism, or euthyroidism (normal level of hormones) seen when intake of iodine too low

26. Adrenal Gland disorders Cushing’s Syndrome: hypersecretion of cortisol caused by tumors that secrete – cortisol (in adrenal cortex) – ACTH  stimulates more cortisol production in adrenal cortex muscle wasting  spindly arms & legs, “moon” face, “buffalo hump” red face ~80% have hypertension

27. Adrenal gland disorders Addison’s Disease: hyposecretion of glucocorticoids & aldosterone most are autoimmune: antibodies cause adrenal cortex destruction or block binding of ACTH to its receptors TB can destroy adrenal cortex symptoms: (after 90% of cortex destroyed) mental lethargy, anorexia, N/V, wt loss, hypotension, hypoglycemia, muscular weakness

29. Pancreatic islet disorders Diabetes mellitus: (honey-sweetened) inabillity to use or produce insulin 4 th leading cause death in USA blood glucose levels high  glucosuria 3 polys: polyuria, polydipsia, polyphagia

30. Diabetes Mellitus Type 1: autoimmune abys destroy beta cells – mostly develops <20 yrs old – most common in northern European heritage – cells starved for glucose so switch to breaking down fatty acids  ketone production  ketoacidosis  untx’d  death – transport of lipids from adipocytes  plaque formation in walls of arteries = atherosclerosis – excess glucose attaches to proteins in lens  catarracts – small vessel disease: blindness, kidney failure, amputation of toes  legs, impotence

31. Diabetes Mellitus Treatment self-monitoring of blood glucose levels  injections of insulin Diet: – 45 – 50% carbohydrates – <30% fats Exercise

32. Type 2 Diabetes non-insulin-dependent diabetes (NIDDM) more common (90% of all cases) typically occurs in obese people > 35 yrs old – #s children diagnosed increasing many control it with diet, exercise, wt loss oral hypoglycemic drugs – stimulates secretion of insulin from beta cells