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Lecture Outline Anatomy and Physiology II Student Outline – The Endocrine System The Endocrine System 1. Introduction A. Endocrine Glands • Endocrine vs. Exocrine Glands B. Hormones C. Target Tissues / Cells 2. Basic Functions A. Maintenance of Homeostasis B. Regulatory Functions i. Growth ii. Development iii. Reproductive Matters 3. Biochemistry of Hormones A. Steroids CH3 CH3 CH2OH CH C O Cortisol CH CH2 3 OH CH2 CH CH OH CH 3 O 2 2 Cholesterol CH CH C O 3 H CH3 C HO HO CH 3 Aldosterone HO HO B. Amines Radical Group OH R O Tyrosine CH Amino Group NH2 C C Acid Group 2 O NH2 C C OH OH H H Basic Amino Acid H OH H H OH OH OH Norepinephrine Epinephrine NH2 C C OH NH2 C C C OH H H H H Page 1 Anatomy and Physiology II Student Outline – The Endocrine System C. Peptides • Antidiuretic Hormone • Oxytocin Oxytocin Antidiuretic Hormone Tyr Tyr Cys Cys Ileu Phe Glu Glu Cys Pro Leu Gly Cys Pro Arg Gly Asp Asp D. Proteins E. Glycoproteins 4. Feedback Control System A. Negative Feedback System (See Endocrine Pathways Handout: “Control Paradigm (Negative Feedback System)) i. Example: (See Endocrine Pathways Handout: “Negative Feedback Example”) B. Positive Feedback System (See Endocrine Pathways Handout: “Positive Feedback Example”) i. Child Birth and Oxytocin Page 2 Anatomy and Physiology II Student Outline – The Endocrine System 5. Mechanisms of Hormone Control A. Fixed-Membrane-Receptor Mechanism ii. Mechanism Inactive ATP Enzyme 1 Inactive cAMP Active Enzyme 2 Enzyme 1 (Secondary Active Messenger) Enzyme 2 Inactive Inactive Enzyme 4 ActiveEnzyme 3 Enzyme 3 Altered Active Cell Function Enzyme 4 ii. Examples B. Mobile-Receptor Mechanism C D F B E G A 6. Pituitary Gland A. Posterior Lobe (Neurohypophysis) Page 3 Anatomy and Physiology II Student Outline – The Endocrine System i. Neurosecretory Cells • ADH Supraoptic Nucleus ! ADH • Oxytocin Paraventricular Nucleus ! Oxytocin • Infundibulum ii. Hormones of the Neurohypophysis a. Antidiuretic Hormone (ADH) (or Vasopressin) • (See Endocrine Pathways Handout: “Water Balance and Antidiuretic Hormone (ADH)”) • Diuretic • Antidiuretic b. Oxytocin • (See Endocrine Pathways Handout: “Positive Feedback Example”) • Myoepithelial Cells • Positive Feedback Mechanism B. Anterior Lobe (Adenohypophysis) Hypothalamus secretes stimulating Hormones Hypothalamic-hypopheseal Portal Vein Pituitary Gland in response to stimulating hormones secretes Anterior Pituitary Gland tropic or non-tropic hormones into the blood stream. i. Hypothalamic-Hypophyseal Portal System ii. Hormones of the Adenohypophysis • Tropic and Non-tropic Hormones Page 4 Anatomy and Physiology II Student Outline – The Endocrine System Endocrine Gland Tropic Hormone Endocrine Gland Endocrine Gland Non-tropic Hormone Target Target Tissue Tissue ** Response ** ** Response ** i. Non-Tropic Hormones a. Growth Hormone (GH) * (See Endocrine Pathways Handout: “Growth Hormone”) • Nontropic. • Anabolic Effect • Amino Acid Uptake Increase • Fat Metabolism • Epiphyseal Plate * Dwarfism * Acromegaly • Mechanism * Growth-Hormone Releasing Hormone (GHRH) * Growth-Hormone Inhibiting Hormone (GHIH) ii. Some Tropic Hormones a. Prolactin • Females * Mammary Gland Development * Milk Production • Males b. Follicle-Stimulating Hormone (FSH) • Females * Follicle Development • Males c. Luteinizing Hormone (LH) • Females * Ovulation • Males * Interstitial Cells * Testosterone * Gonadotropin-Releasing Hormone (GnRH) g. Melanocyte-Stimulating Hormone (MSH) Page 5 Anatomy and Physiology II Student Outline – The Endocrine System 7. Thyroid Gland (Follicles of gland) * (See Endocrine Pathways Handout: “Thyroxin and the Basal Metabolic Rate (BMR)”) page #7 (??) • Follicular Cells A. Thyroxine (T4) and Triiodothyronine (T3) i. Structure a. Follicles b. Colloid ii. Synthesis a. Tyrosine b. Iodine iii. Function a. Increase Metabolism b. Calorigenic Effect iv. Thyroid Malfunction a. Hyperthyroidism Page 6 Anatomy and Physiology II Student Outline – The Endocrine System b. Hypothyroidism c. Goiter * (Pull out Handout: (Iodine and Goiter”) v. Synthesis of Thyroid Hormone vi. An Alternative diagram for Thyroid regulation: Metabolic Rate Slows Down Thyroid Secretes Decreases Neg. Feedback Hypothalamus Releases Less Thyroxine More TRH Pituitary Secretes Pituitary Secretes Less TSH More TSH Hypothalamus Releases Increases Neg. Feedback Thyroid Secretes Less TRH More Thyroxin Metabolic Rate Speeds Up 8. Parathyroid Glands AND Thyroid Gland (Parafollicular cells NOT Follicles) * (See Endocrine Pathways Handout: “Calcium Regulation in the Blood”) A. Parathyroid Hormone i. Function ii. Mechanisms a. Calcium Reabsorption b. Kidney Reabsorption c. Digestive Absorption of Calcium B. Parafollicular Cells of Thyroid Gland 9. Adrenal Glands * (See Endocrine Pathways Handout: Page 7 Anatomy and Physiology II Student Outline – The Endocrine System “Adrenal Gland and Stress”) • Medulla • Cortex A. Adrenal Cortex i. General Information ii. Anatomy a. Zona Glomerulosa b. Zona Fasciculata c. Zona Reticularis iii. Hormones of the Adrenal Gland a. Glucocorticoids • Gluconeogenesis • Cortisol and Corticosterone • Corticotropin-Releasing Hormone (CRH) b. Mineralocorticoid • Aldosterone B. Adrenal Medulla * (Again, see Endocrine Pathways Handout: “Adrenal Gland and Stress”) i. Hormones a. Epinephrine b. Norepinephrine ii. Stress and the Adrenal Cortex Page 8 Anatomy and Physiology II Student Outline – The Endocrine System STRESS Adrenal medulla Sympathetic secretes epinephrine nerve Hypothalamus and norepinephrine impulses Blood Glucose Heart Rate Respiration Secretes CRH Rises Increases Rate increases (Corticotropin Rel. Hor.) Blood flow to Blood Pressure Bronchioles skeletal muscles Rises dilate Adenohypophysis increases secretes ACTH Adrenal cortex secretes cortisol Protein is used Gluconeogenesis Insulin to brain for energy and for energy to ensure tissue repair glucose supply 10. Pancreas * (See Endocrine Pathways Handout: “Glucose Regulation”) A. Introduction i. Mixed Gland a. Exocrine Gland b. Endocrine Gland • Pancreatic Islets B. Hormones i. Glucagon a. Alpha Cells ii. Insulin - a peptide a. Beta Cells Page 9 Anatomy and Physiology II Student Outline – The Endocrine System 11. Gonads • Ovaries • Testes A. Male Sex Hormones i. Testosterone ii. Luteinizing Hormone (LH) iii. Follicle-Stimulating Hormone (FSH). iv. Inhibin B. Female Sex Hormones i. Estrogens ii. Relaxin i. Follicle-stimulating hormone ii. Luteinizing hormone 12. Other Sources of Hormones A. Kidneys i. Renin ii. Erythropoietin * (See Endocrine Pathways Handout: “Oxygen Carrying Capacity of Blood”) B. Pineal Gland i. Melatonin C. Thymus Gland D. Digestive System i. Gastrin ii. Secretin iii. Cholecystokinin E. Placenta Page 10 .
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