CHAPTER 45 HORMONES & ENDOCRINE SYSTEM Long Distance Regulators I. Endocrine system A. Hormones Blood/Hemolymph II. Nervous system A. Neurons Signaling molecules I. Types of signaling A. Endocrine signaling 1. Blood stream Target any cell in body B. Paracrine signaling 1. Diffuse locally affect local cells only C. Autocrine signaling 1. Local regulators that affect cells that release D. Synaptic signaling 1. Short distance E. Neroendocrine 1. Blood stream Target any cell in body

II. Classes of hormomes A. H2O soluble 1. Polypeptides a. Proteins/peptides 2. Amines a. Amino Acids B. Lipid soluble 1. Steroids a. Lipids III. Cellular response pathways A. Water soluble hormones 1. Signal transduction pathways 2. Travel freely through bloodstream 3. Cannot enter directly through plasma membrane B. Lipid soluble hormones 1. Enter directly through plasma membrane 2. Must attach to transport protein to travel through blood

IV. Multiple effects of hormones

45.2 Negative feedback & antogonistic hormone pairs I. Simple hormone pathways A. Negative feedback

B. Example Insulin & glucagon: Control of blood glucose 1. Insulin decrease blood glucose levels a. Target body cells outside of brain 1. Increase uptake & storage 2. decrease glycogen breakdown in liver 2. Glucagon Increase blood glucose levels a. Target Liver cells

3. Diabetes Mellitus a. Inability to control glucose homeostasis 1. Blood glucose levels increase 2. Body is incapable of removing glucose for blood a. Lack insulin production Type I b. Decreases response to insulinType II b. Type I (insulin-dependant) inherited 1. “Juvenile” diabetes 2. Autoimmune disorder a. Immune system destroys beta cells of pancrease 1. Insulin not made 3. Insulin injections c. Type II (non-insulin dependent) 1. “Adult onset” diabetes 2. Target cells fail to respond to insulin a. Insulin is produced 3. Heredity, obesity, lack of exercise 4. Controlled through diet

45.3 Endocrine & Nervous System I. Coordination in vertebrates A. Hypothalamus 1. Endocrine gland 2. Receives nerve signals from body and brain a. Initiates endocrine signaling b. Signaling travels to pituitary gland B. Pituitary glands 1. Posterior pituitary gland a. Stores and secretes 2 hormones synthesized by hypothalamus b. Oxytocin 1. Mammalian milk release during nursing 2. Uterine contraction during birth 3. Positive feedback c. Antidiuretic hormone (ADA) 2. Anterior pituitary gland a. Synthesizes and secretes a variety of hormones (Table 45.1) b. Controlled by the hypothalamus 1. Releasing or inhibiting hormone

45.4 Endocrine Glands & their Hormones I. Thyroid Hormone A. Regulated by Thyroid Stimulating Hormone (TSH) B. Controls a variety of metabolic processes C. Iodine a major component to thyroid hormones 1. Deficiencies can result in a variety of metabolic disorders 2. Dietary iodine crucial for proper thyroid function a. Seafood & iodized salt II. Parathyroid hormone A. Controls blood Ca2+

III. Adrenal Hormones: Response to stress A. Epinephrine (adrenalin) and Norepinephrine 1. the “fight or flight” response 2. Affects a. Increase available energy 1. Increase glycogen breakdown in liver and skeletal muscle 2. Increase glucose release by liver 3. Release of FA from fat cells b. Increase both HR and stroke volume c. Dilate bronchioles d. Alter blood flow 1. decrease to skin, digestive organs, and kidneys 2. increase to heart, brain, skeletal muscles