1. Exercise 18 Endocrine System Glucometer Portland Community College BI 232

2. The endocrine system Diverse collection of organs and tissues that contain endocrine glands. Glands secrete chemicals called hormones into blood capillaries Hormones are transported to target cells at a distant location Hormone binds to a specific receptor and the cell responds to message. 2

3. Endocrine and Exocrine Exocrine glands secrete substances into ducts, which transport the secretions internal cavities of organs or to surface of the skin. 3

4. Neuroendocrine effect The endocrine system operates in conjunction with the nervous system to maintain homeostasis and to ensure that bodily functions are carried out efficiently. Nerve impulses can affect the release of hormones and hormones can regulate nerve impulses 4

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6. Endocrine Organs in Head Pineal gland Secrets: Melatonin Involved in circadian rhythms Day  melatonin, Night  melatonin Produces sleepiness 6

7. Endocrine Organs in Head Hypothalamus produces a number of releasing hormones and inhibiting hormones. Stored in posterior pituitary ADH (antidiuretic hormone) Reduces urine output by increasing water reabsorption in the kidney Plays small role in blood pressure regulation Oxytocin Causes uterine contractions in labor Causes milk let down in lactating mothers 7

8. Endocrine Organs in Head Hypophysis ACTH (adrenocorticotropic hormone) Regulates the activity of the cortex of the adrenal gland TSH (thyroid stimulating hormone) Stimulates production and release of thyroid hormone GH (growth hormone) Stimulates growth of bones, cartilage, muscle Timing and amount released determines body size 8

9. Endocrine Organs in Head PRL (prolactin) Stimulates breast development Promotes and maintains lactation after childbirth FSH (follicle stimulating hormone) Causes formation of ovarian follicles and stimulates them to produce estrogen Stimulates sperm development in men LH (luteinizing hormone) Initiates ovulation, maintains corpus luteum Regulates testosterone production in males 9

10. 10 Pituitary Histology

11. Endocrine Organs in Neck Thyroid gland secretes: Thyroid Hormone Regulates metabolic rate of the entire body Important in development of the nervous system Calcitonin Decreases bone reabsorption, lowering serum calcium levels PTH (parathyroid hormone) Increases serum calcium Decreases serum phosphorus 11

12. 12 Thyroid Histology

13. 13 Thyroid Histology Follicular cells produce the colloid (contains precursors to thyroid hormone) Parafollicular cells secrete calcitonin

14. 14 Parathyroid Histology

15. Endocrine organs in thoracic Heart: If blood volume is elevated above normal, cardiac muscle cells in the heart was secrete natriuretic peptides. Act on the kidneys to promote the loss of sodium ions and water. The thymus gland produces hormones called thymosins that promote maturation of T- lymphocytes that coordinate the body’s immune response. 15

16. Endocrine Organs located in abdominopelvic cavity Pancreas secretes: Insulin Released in response to high blood sugar Increases cellular absorption of glucose Increases rate of lipogenesis and formation of glycogen in the liver Glucagon Released in response to low blood sugar Elevates blood glucose levels by promoting the breakdown of glycogen. 16

17. 17 Pancreas Acinar cells secrete digestive enzymes (exocrine) Islet cells secrete insulin (beta cells) and glucagon (alpha cells)

18. 18 Adrenal Glands

19. Endocrine Organs located in abdominopelvic cavity Adrenal glands secrete: Glucocorticoids (Cortisone) Released in response to stress Increases formation of glucose from protein and fat breakdown Decreases inflammation Aldosterone Increases blood volume by causing kidneys to retain sodium (where sodium goes water goes too) in exchange for potassium Increased blood volume will increase blood pressure 19

20. Endocrine Organs located in abdominopelvic cavity Androgens Are male sex hormones that are produced in small quantities and converted to estrogens (female sex hormones) when they enter the blood Epinephrine & Norepinephrine Fight or flight response Increase heart rate, increase skeletal muscle blood flow, decrease skin blood flow 20

21. Hormones from the Kidneys 21 Erythropoietin Stimulates RBC production Calcitriol Stimulates calcium and phosphate absorption Stimulates calcium release from bone Inhibits PTH secretion

22. 22 Adrenal Histology

23. 23 Adrenal Cortex Zona Glomerulosa: Aldosterone Zona Fasiculata: Glucocorticoids (Cortisone) Zona Reticularis: Androgens

24. Gonads Ovaries in females produce estrogens Testes in males produce testosterone 24

25. Ovary Have an outer cortex that contains ovarian follicles at various stages of development. Each follicle contains a developing egg cell called an oocyte Inner medulla is a region of loose connective tissue 25

26. Testis Tunica albuginea is a fibrous connective tissue covering. Connective tissue partitions derived from the tunica albuginea divide the testes into lobules 26

27. Testes Each lobule of the testes are three or four seminiferous tubules. Collectively these cells are called spermatogenic cells. The interstitial areas contain the interstitial (Leydig) cells. 27

28. 28 Diabetes Type 1: Insulin Dependent Diabetes AKA: juvenile diabetes Caused by a lack of insulin Autoimmune disorder Immune system destroys beta cells in the pancreas

29. 29 Diabetes Type 2: Non-Insulin Dependent Caused by an insensitivity of cells to insulin. Diabetes mellitus marked by hyperglycemia  urine production (polyuria)  thirst (polydipsia)  eating (polyphagia)

30. 30 Diagnosing Diabetes Mellitus Normal blood glucose levels: 70-100 mg/dl Diabetes mellitus: A fasting glucose level above 140 mg/dl on two separate occasions, or A blood sugar over 200 mg/dl 2 hours after oral glucose tolerance test with 75gm of glucose Impaired Glucose Tolerance (Pre-Diabetes) A fasting glucose level between 100-126 mg/dl on two separate occasions, or A blood sugar between 140-200 mg/dl 2 hours after oral glucose tolerance test with 75gm of glucose

31. 31 The End