Chapt13 endocrine

  • Published on
    19-May-2015

  • View
    2.759

  • Download
    0

Embed Size (px)

Transcript

<ul><li> 1. Holes Human Anatomy and Physiology Twelfth Edition ShierButlerLewisChapter13 Endocrine System Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display.</li></ul><p> 2. 13.1: Introduction </p> <ul><li>The endocrine system assists the nervous system with communication and control of the body </li></ul><ul><li>The cells, tissues, and organs are called endocrine glands</li></ul><ul><li><ul><li>They are ductless </li></ul></li></ul><ul><li><ul><li>They use the bloodstream </li></ul></li></ul><ul><li><ul><li>They secrete hormones </li></ul></li></ul><ul><li><ul><li>There are also similar glands called paracrine and autocrine glands that are quasi-endocrine </li></ul></li></ul><ul><li>Other glands that secrete substances are the exocrine glands</li></ul><ul><li><ul><li>They have ducts </li></ul></li></ul><ul><li><ul><li>They deliver their products directly to a specific site </li></ul></li></ul><p> 3. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hormone secretion (a) (b) Blood flow Skin Duct Thyroid gland Endocrine gland Endocrine cell Exocrine gland (sweat gland) Exocrine cells 4. 13.2: General Characteristics of the Endocrine System </p> <ul><li>The endocrine and nervous systems communicate using chemical signals </li></ul><ul><li><ul><li>Neurons release neurotransmitters into a synapse affecting postsynaptic cells </li></ul></li></ul><ul><li><ul><li>Endocrine glands release hormones into the bloodstream to specific target cell receptors </li></ul></li></ul><p> 5. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) (b) Nerve impulse Bloodstream Neuron transmits nerve impulse Glandular cells secrete hormone into bloodstream Neurotransmitter released into synapse Post- synaptic cell responds Target cells (cells with hormone receptors) respond to hormone Hormones have no effect on other cells 6. 7. 13.3: Hormone Action </p> <ul><li>Hormones are released into the extracellular spaces surrounding endocrine cells </li></ul><p>CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hypothalamus Pituitary gland Thyroid gland Thymus Adrenal gland Pancreas Parathyroid gland Pineal gland Kidney Testis (in male) Ovary (in female) 8. Chemistry of Hormones </p> <ul><li>Chemically, hormones are either: </li></ul><ul><li><ul><li>Steroid or steroid-like hormones such as: </li></ul></li></ul><ul><li><ul><li><ul><li>Sex hormones </li></ul></li></ul></li></ul><ul><li><ul><li><ul><li>Adrenal cortex hormones </li></ul></li></ul></li></ul><ul><li><ul><li>Non-steroid hormones such as: </li></ul></li></ul><ul><li><ul><li><ul><li>Amines </li></ul></li></ul></li></ul><ul><li><ul><li><ul><li>Proteins </li></ul></li></ul></li></ul><ul><li><ul><li><ul><li>Peptides </li></ul></li></ul></li></ul><ul><li><ul><li><ul><li>Glycoproteins </li></ul></li></ul></li></ul><p> 9. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. O H 3 C (a) Cortisol (d) Oxytocin OH HO C HO (b) Norepinephrine H H OH H C NH 2 C H H C C H H C H H C H H H H H H C C C C C (e) Prostaglandin PGE 2 H OH H H H OH C H H H H C H C C H H C C H H C O OH H H H H C HO H 3 C C O C O C Ala Val Asp His Ser Arg Gly Arg Arg Asp Ser Glu Pro Arg Asp Ala Ser Glu Glu Phe Ile Gly Asp His His Ser Leu Leu Met Ala Pro Pro Ala Ala Glu Glu Leu Asp Ser Gly Glu Glu Glu Arg Gly Cys Cys Asp Glu Ile Pro Leu Gly His Ileu Met Glu Ser Phe Ala Leu Glu Ser Asp Ile Leu Leu Leu Asp Glu Leu Gly Glu S S CH 2 OH Val Lys Lys Lys Lys Val Lys Lys Lys Val Lys Tyr Val Val Lys Lys Lys Try Val Tyr (c) Parathyroid ho rm one (PTH) 10. 11. 12. Action of Hormones </p> <ul><li>Steroid Hormones </li></ul><p>Hormone molecule Ribosome Nucleus 1 2 3 5 4 Newly forming protein molecule Cell membrane Hormone-receptor complex Intracellular receptor molecule mRNA mRNA DNA CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. 13. Action of Hormones </p> <ul><li>Non-steroid Hormones </li></ul><p>Cell membrane G protein Cytoplasm Nucleus ATP cAMP 1 2 3 5 4 Membrane-bound receptor molecule Nonsteroid hormone molecule Hormone- receptor complex Adenylate cyclase Protein kinases (inactive) Substrate (inactive) Protein kinases (active) Substrate (active) Cellular changes CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. 14. 13.1 Clinical Application Using Hormones to ImproveAthletic Performance 15. Prostaglandins </p> <ul><li>Prostaglandins: </li></ul><ul><li><ul><li>Are paracrine substances </li></ul></li></ul><ul><li><ul><li>Are very potent in small amounts </li></ul></li></ul><ul><li><ul><li>Are not stored in cells but synthesized just before release </li></ul></li></ul><ul><li><ul><li>Rapidly inactivate </li></ul></li></ul><ul><li><ul><li>Regulate cellular responses to hormones </li></ul></li></ul><ul><li><ul><li>Can activate or inhibit adenylate cyclase </li></ul></li></ul><ul><li><ul><li><ul><li>Controls cAMP production </li></ul></li></ul></li></ul><ul><li><ul><li><ul><li>Alters a cells response to hormones </li></ul></li></ul></li></ul><ul><li><ul><li>Has a wide variety of effects </li></ul></li></ul><p> 16. 13.4: Control ofHormonal Secretions </p> <ul><li>Primarily controlled by negative feedback mechanism </li></ul><ul><li>Hormones can be short-lived or may last for days </li></ul><ul><li>Hormone secretions are precisely regulated </li></ul><p> 17. Control Sources CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. too high too low Control center Endocrine gland inhibited. Receptors Hormone control mechanism senses change. Effectors Hormone secretion decreased. Stimulus Hormone levels rise or controlled process increases. Response Hormone levels return toward normal. Normal hormone levels Stimulus Hormone levels drop or controlled process decreases. Response Hormone levels return toward normal. Receptors Hormone control mechanism senses change. Effectors Hormone secretion increased. Control center Endocrine gland stimulated. 18. Control Sources CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Nervous system (a) (b) (c) Target cells Action Target cells Action Anterior pituitary gland Action Hypothalamus Peripheral endocrine gland Target cells Endocrine gland Changing level of substance in plasma Endocrine gland 19. 13.5: Pituitary Gland </p> <ul><li>Lies at the base of the brain in the sella turcica </li></ul><ul><li>Consists of two distinct portions: </li></ul><ul><li><ul><li>Anterior pituitary (adenohypophysis) </li></ul></li></ul><ul><li><ul><li>Posterior pituitary (neurohypophysis) </li></ul></li></ul><p> 20. Optic nerve Sphenoid bone Hypothalamus Optic chiasma Sella turcica Third ventricle Trochlear nerve Basilar artery Anterior cerebral artery Pituitary stalk (Infundibulum) Anterior lobe of pituitary gland Sphenoidal sinus Posterior lobe of pituitary gland Oculomotor nerve CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. 21. Anterior Pituitary Hormones </p> <ul><li>Hypothalamic releasing hormones stimulate cells of anterior pituitary to release hormones </li></ul><ul><li>Nerve impulses from hypothalamus stimulate nerve endings in the posterior pituitary gland to release hormones </li></ul><p>Hypophyseal veins Optic chiasma Capillary bed Posterior lobe of pituitary gland Third ventricle Hypothalamus Anterior lobe of pituitary gland Capillary bed Hypophyseal portal veins Secretory cells of anterior pituitary gland Neurosecretory cells that secrete releasing hormones Superior hypophyseal artery Neurosecretory cells that secrete posterior pituitary hormones Inferior hypophyseal artery Sella turcica of sphenoid bone CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. 22. Anterior pituitary Peripheral endocrine gland Hypothalamus Target cells (Hormone 3) + + + Inhibition Stimulation Releasing hormone (Hormone 1) Anterior pituitary hormone (Hormone 2) CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Michael Ross/Photo Researchers, Inc. Secretory cells 23. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Thyroid Mammary gland Ovary Testis Bone Muscle Hormones from Anterior Pituitary Hormones from Hypothalamus GHRH Growthhormone- releasing hormone SS Somatostatin PRF Prolactin- releasing factor PIH Prolactin- release inhibitinghormone TRH Thyrotropin- releasing hormone CRH Corticotropin- releasing hormone GnRH Gonadotropin- releasing hormone GH Growth hormone PRL Prolactin TSH Thyroid- stimulating hormone ACTH Adrenocorticotropic hormone LH Luteinizing hormone FSH Follicle- stimulating hormone Adipose tissue Adrenal cortex 24. 13.2 Clinical Application Growth Hormone Ups and Downs 25. Posterior Pituitary Hormones </p> <ul><li>Structurally consists of nerve fibers and neuroglia v. glandular epithelial cells of the anterior pituitary gland </li></ul><ul><li>The nerve fibers originate in the hypothalamus </li></ul><ul><li>Two hormones are produced: </li></ul><ul><li><ul><li>Antidiuretic hormone (vasopressin) </li></ul></li></ul><ul><li><ul><li>Oxytocin </li></ul></li></ul><p> 26. 27. 13.6: Thyroid Gland </p> <ul><li>The thyroid gland has two lateral lobes and lies just below the larynx </li></ul><ul><li>It produces three hormones: </li></ul><ul><li><ul><li>T3 (thyroxine) </li></ul></li></ul><ul><li><ul><li>T4 (triiodothyronine) </li></ul></li></ul><ul><li><ul><li>Calcitonin </li></ul></li></ul><p> 28. Structure of the Gland CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Follicular cells Colloid Extrafollicular cells Fred Hossler/Visuals Unlimited Larynx Colloid Isthmus (a) (b) Thyroid gland Follicular cell Extrafollicular cell CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. 29. Thyroid Hormones CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. OH O I I CH 2 I I OH O I CH 2 I I NH 2 CHCOOH NH 2 CHCOOH Thyroxine (T 4 ) Triiodothyronine (T 3 ) 30. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Mediscan/Visuals Unlimited Mediscan/Visuals Unlimited Mediscan/Visuals Unlimited 31. 13.7: Parathyroid Glands </p> <ul><li>The parathyroid glands are on the posterior surface of the thyroid gland </li></ul><ul><li>There are typically four parathyroid glands </li></ul><ul><li>It secretes one hormone: </li></ul><ul><li><ul><li>PTH (parathyroid hormone or parathormone) </li></ul></li></ul><p> 32. Structure of the Glands Posterior view Esophagus Pharynx Thyroid gland Parathyroid glands Trachea CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Secretory cells Capillaries CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. R. Calentine/Visuals Unlimited 33. Parathyroid Hormone CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Liver Intestinal enzymes Ultraviolet light in skin Kidney Stimulated by PTH Hydroxycholecalciferol Foods Ca +2 Ca +2 Ca +2 Cholesterol Provitamin D Vitamin D (Cholecalciferol) Also obtained directly from foods Dihydroxycholecalciferol (active form of vitamin D) Controls absorption of calcium in intestine 34. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. PTH Ca +2 + PTH PTH Ca +2 + Ca +2 Bloodstream Stimulation Inhibition Release into bloodstream Parathyroid glands (on posterior of thyroid gland) Decreased blood calcium stimulates parathyroid hormone secretion Increased blood calcium inhibits PTH secretion Kidneys conserve Ca +2andactivate Vitamin D Bone releases Ca +2 Intestine absorbs Ca +2 Active Vitamin D 35. 36. 13.8: Adrenal Glands </p> <ul><li>The adrenal glands are closely associated with the kidneys </li></ul><ul><li>The gland sits like a cap on each kidney </li></ul><ul><li>Hormones are secreted from two different areas of the gland, the adrenal cortex and the adrenal medulla </li></ul><ul><li>Numerous hormones are secreted by the adrenal glands </li></ul><p> 37. Structure of the Glands Cortex Medulla Capsule Zona glomerulosa Zona fasciculata Zona reticularis Chromaffin cells CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ed Reschke Adrenal gland Kidney Adrenal cortex (a) Zonalomerulosa Connective tissue capsule (b) Zona fasciculata Zona reticularis Adrenal medulla Adrenal cortex Adrenal medulla Surface of adrenal gland CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. 38. Hormones of the Adrenal Medulla 39. Hormones of the Adrenal Cortex 40. 13.3 Clinical Application Disorders of the Adrenal Cortex 41. 13.1 From Science to Technology Treating Diabetes 42. 13.9: Pancreas </p> <ul><li>The pancreas has two major types of secretory tissue </li></ul><ul><li>This is why it is a dual functioning organ as both an exocrine gland and endocrine gland </li></ul><ul><li>Three hormones are secreted from the islet cells: </li></ul><ul><li><ul><li>Alpha cells secrete glucagon </li></ul></li></ul><ul><li><ul><li>Beta cells insulin </li></ul></li></ul><ul><li><ul><li>Delta cells secrete somatostatin </li></ul></li></ul><p> 43. Structure of the Gland CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pancreatic islet (Islet of Langerhans) From Kent M. Van De Graaff and Stuart Ira Fox, Concepts of Human Anatomy and Physiology, 2nd ed.1989 Wm. C. Brown Publishers, Dubuque, Iowa.All Rights Reserved.Reprinted with permission CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Gallbladder Common bile duct Pancreatic duct Pancreas Duct Capillary Small intestine Digestive enzyme- secreting cells Pancreatic islet (Islet of Langerhans) Hormone-secreting islet cells Know 44. Hormones of the Pancreatic Islets 45. CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. too high too low Control center Beta cells secrete insulin Receptors Beta cells detect a rise in blood glucose Effectors Insulin Promotes movementof glucose into certain cells Stimulates formation of glycogen from glucose Stimulus Rise in blood glucose Response Blood glucose drops toward normal (and inhibits insulin secretion) Normal blood glucose concentration Stimulus Drop in blood glucose Response Blood glucose rises toward normal (and inhibits glucagon secretion) Receptors Alpha cells detect a drop in blood glucose Effectors Glucagon Stimulates cells to break down glycogen into glucose Stimulates cells to convert noncarbohydrates into glucose Control center Alpha cells secrete glucagon 46. 13.4 Clinical Application Diabetes Mellitus 47. 13.10: Other Endocrine Glands </p> <ul><li>Pineal Gland </li></ul><ul><li><ul><li>Secretes melatonin </li></ul></li></ul><ul><li><ul><li>Regulates circadian rhythms </li></ul></li></ul><ul><li>Thymus Gland </li></ul><ul><li><ul><li>Secretes thymosins </li></ul></li></ul><ul><li><ul><li>Promotes development of certain lymphocytes </li></ul></li></ul><ul><li><ul><li>Important in role of immunity </li></ul></li></ul><ul><li>Reproductive Organs </li></ul><ul><li><ul><li>Ovaries produce estrogens and progesterone </li></ul></li></ul><ul><li><ul><li>Testes produce testosterone </li></ul></li></ul><ul><li><ul><li>Placenta produces estrogens, progesterone, and gonadotropin </li></ul></li></ul><ul><li>Other organs : digestive glands, heart, and kidney </li></ul><p> 48. 13.11: Stress and Its Effects </p> <ul><li>Survival depends on maintaining homeostasis </li></ul><ul><li>Factors that change the internal environment are potentially life-threatening </li></ul><ul><li>Sensing such dangers directs nerve impulses to the hypothalamus </li></ul><ul><li>This can trigger a loss of homeostasis </li></ul><p> 49. Types of Stress </p> <ul><li>Two types of stress: </li></ul><ul><li><ul><li>Physical stress </li></ul></li></ul><ul><li><ul><li>Psychological stress </li></ul></li></ul><p> 50. Responses to Stress CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sympathetic impulses CRH released ACTH released Cortisol released Long-term adjustment or resistance stage Increase in blood concentration of amino acids. Increased release of fatty acids. Blood glucose increases. Blood glycerol and fatty acids increase. Heart rate increases. Blood pressure rises. Breathing rate increases. Air passages dilate. Pupils dilate. Anterior pituitary Hypothalamus Adrenal cortex Adrenal medulla Neural signals Hormonal signals Stress results from changes in the external environment Signals from sensory receptors Epinephrine and norepinephrine released Norepinephrine released Short-term fight or flight or alarm stage. Blood flow redistributes. Increased glucose formed from noncarbohydratesamino acids (from proteins) and glycerol (from fats). 51. 52. 13.12: Lifespan Changes </p> <ul><li>Endocrine glands decrease in size </li></ul><ul><li>Muscular strength decreases as GH levels decrease </li></ul><ul><li>ADH levels increa...</li></ul>

Recommended

View more >