Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 1 Endocrine System Chapter 16

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 2 Introduction Endocrine system encompasses the production and secretion of hormones from glands Orme: means “to excite” Hormones: activate (or excite) a specific target cells, causing a response

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 3 Endocrine Anatomy Three glands in head: Pituitary produces hormones that affect other glands & target organs Hypothalamus produces hormones that affect the pituitary gland. Pineal is below hypothalamus & responsible for controlling circadian rhythms, sexual growth, other body functions Three glands in head: Pituitary produces hormones that affect other glands & target organs Hypothalamus produces hormones that affect the pituitary gland. Pineal is below hypothalamus & responsible for controlling circadian rhythms, sexual growth, other body functions

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 4 Pituitary Gland Master Gland Posterior Pituitary glands secretes: Hormones regulate kidneys via reabsorption (ADH) Oxytocin: uterine contractions during labor; lactation in pregnant women Anterior Pituitary Gland secretes: ACTH – stimulates adrenal gland Thyroid Stimulating Hormone – thyroid gland Growth Hormone Prolactin – stimulates mammary gland, make milk Follicle Stimulating Hormone and Luteinizing Hormone – stimulates ovary Posterior Pituitary glands secretes: Hormones regulate kidneys via reabsorption (ADH) Oxytocin: uterine contractions during labor; lactation in pregnant women Anterior Pituitary Gland secretes: ACTH – stimulates adrenal gland Thyroid Stimulating Hormone – thyroid gland Growth Hormone Prolactin – stimulates mammary gland, make milk Follicle Stimulating Hormone and Luteinizing Hormone – stimulates ovary

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 5 Functions of the Endocrine Glands Hypothalamus: In brain, below thalamus gland Links nervous system to endocrine system Regulates water balance, metabolism of fats and carbohydrates, body temperature, appetite, emotions Hypothalamus: In brain, below thalamus gland Links nervous system to endocrine system Regulates water balance, metabolism of fats and carbohydrates, body temperature, appetite, emotions

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 6 Pineal Gland Produces and secretes melatonin Melatonin: helps to regulate sleep-wake cycle; affected by light; linked to puberty and menstrual cycle Produces and secretes melatonin Melatonin: helps to regulate sleep-wake cycle; affected by light; linked to puberty and menstrual cycle

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 7 Thyroid Gland Location: base of neck Produces and secretes three hormones: thyroxine (T 4 ), triiodothyronine (T 3 ), calcitonin Iodine necessary to synthesize T 4, T 3 Trigger rate of metabolism of proteins, fats (lipids), sugars (carbohydrates) throughout body Important for growth and homeostasis of body Location: base of neck Produces and secretes three hormones: thyroxine (T 4 ), triiodothyronine (T 3 ), calcitonin Iodine necessary to synthesize T 4, T 3 Trigger rate of metabolism of proteins, fats (lipids), sugars (carbohydrates) throughout body Important for growth and homeostasis of body

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 8 Parathyroid Glands Para—“across” Two sets of secreting glands Main regulators of calcium levels in blood Draw calcium out of bones to increase it in extracellular fluid Lowers concentration of phosphate s Para—“across” Two sets of secreting glands Main regulators of calcium levels in blood Draw calcium out of bones to increase it in extracellular fluid Lowers concentration of phosphate s

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 9 Adrenal Glands Medulla - synthesizes and secretes catecholamines: norepinephrine/epinephrine Cortex - three types of hormones: Glucocorticoids: reduce inflammation, increase capacity to deal with stressful situations Mineralocorticoids: regulate secretion of both water and salt in kidney Sex hormones: androgens or estrogens Medulla - synthesizes and secretes catecholamines: norepinephrine/epinephrine Cortex - three types of hormones: Glucocorticoids: reduce inflammation, increase capacity to deal with stressful situations Mineralocorticoids: regulate secretion of both water and salt in kidney Sex hormones: androgens or estrogens

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 10 Endocrine Anatomy (Continued) Pancreas - largest gland; produces and secretes: digestive juices two hormones Insulin Glucagon Pancreas - largest gland; produces and secretes: digestive juices two hormones Insulin Glucagon

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 11 Endocrine Anatomy Reproduction: Ovaries (female): progesterone, estrogen Males: testosterone Responsible for gender characteristics Anterior pituitary gland releases FSH  increases estrogen  causes LH to be secreted  ovulation Reproduction: Ovaries (female): progesterone, estrogen Males: testosterone Responsible for gender characteristics Anterior pituitary gland releases FSH  increases estrogen  causes LH to be secreted  ovulation

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 12 Description of Hormones (Continued) Glands: two mechanisms of action (exocrine or endocrine) Endocrine glands: enter bloodstream to get to target cells Exocrine glands: sent to target organ or tissue via tube or duct (skin -> duct -> sweat gland) Glands: two mechanisms of action (exocrine or endocrine) Endocrine glands: enter bloodstream to get to target cells Exocrine glands: sent to target organ or tissue via tube or duct (skin -> duct -> sweat gland)

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 13 Conditions of the Pituitary and Hypothalamus Gland & Their Treatments Hyperfunction of pituitary gland - caused by tumor growths Increase of growth hormone (GH): Giantism - present in children (elongated bones, height of 8 ft) Acromegaly - present in adults (increased size of head, tongue, nose, hands, feet, toes) Hyperfunction of pituitary gland - caused by tumor growths Increase of growth hormone (GH): Giantism - present in children (elongated bones, height of 8 ft) Acromegaly - present in adults (increased size of head, tongue, nose, hands, feet, toes)

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 14 Hypofunction of pituitary gland - decrease in hormones Dwarfism: congenital defect Simmonds’ disease: adults; lack of menstruation in women; impotence in men Lack of ADH (from lesions, tumors, infections); infection in or on hypothalamus, posterior pituitary gland Treated with medication for life Hypofunction of pituitary gland - decrease in hormones Dwarfism: congenital defect Simmonds’ disease: adults; lack of menstruation in women; impotence in men Lack of ADH (from lesions, tumors, infections); infection in or on hypothalamus, posterior pituitary gland Treated with medication for life Conditions of the Pituitary and Hypothalamus Gland and Their Treatments (Cont)

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 15 Conditions of the Thyroid and Their Treatments Hyperthyroidism: excess of thyroid hormone Causes: Graves’ disease (autoimmunity), goiter Radioactive iodine decreases nodules in goiters Radiation destroys part of thyroid gland Hyperthyroidism: excess of thyroid hormone Causes: Graves’ disease (autoimmunity), goiter Radioactive iodine decreases nodules in goiters Radiation destroys part of thyroid gland

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 16 Osteoporosis Management and Treatment Treatment for osteoporosis: Fosamax, Calcimar Prevention of osteoporosis: must be started early in life - lifestyle changes, exercise, diet, smoking cessation Exercise, calcium, vitamin D: increase bone density Medications like Fosamax increase bone density Long-term use of corticosteroids, medroxyprogesterone, excessive thyroid hormones promote osteoporosis Treatment for osteoporosis: Fosamax, Calcimar Prevention of osteoporosis: must be started early in life - lifestyle changes, exercise, diet, smoking cessation Exercise, calcium, vitamin D: increase bone density Medications like Fosamax increase bone density Long-term use of corticosteroids, medroxyprogesterone, excessive thyroid hormones promote osteoporosis

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 17 Conditions of the Pancreas Gland and Their Treatments Two categories of diabetes mellitus: Insulin-dependent or Type 1 Requires SC injections of insulin for rest of life Non–insulin-dependent or Type 2 Treatment: lifestyle changes; oral medications Causes of diabetes: Inability of pancreas to secrete insulin Resistance to insulin that affects the levels of glucose (results in hyperglycemia) Can lead to renal disease, blindness, gangrene (leads to amputation of extremities) Two categories of diabetes mellitus: Insulin-dependent or Type 1 Requires SC injections of insulin for rest of life Non–insulin-dependent or Type 2 Treatment: lifestyle changes; oral medications Causes of diabetes: Inability of pancreas to secrete insulin Resistance to insulin that affects the levels of glucose (results in hyperglycemia) Can lead to renal disease, blindness, gangrene (leads to amputation of extremities)

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 18 Conditions of the Pancreas Gland and Their Treatments (Continued) Two main types of insulin for insulin dependent: Natural insulin - taken from animals (pigs, cows) Synthesized human insulin Fast Acting Intermediate Acting Two main types of insulin for insulin dependent: Natural insulin - taken from animals (pigs, cows) Synthesized human insulin Fast Acting Intermediate Acting

Copyright © 2007, 2004 by Saunders, an imprint of Elsevier Inc. All rights reserved. 19 New Combination Agents Therapy for Type 2 diabetes: multiple drug therapy Four new combinations for NIDDM: Glucovance (metformin/glyburide) Metaglip (glipizide/metformin) Avandamet (rosiglitazone/metformin) Actoplus Met (pioglitazonel/metformin) Therapy for Type 2 diabetes: multiple drug therapy Four new combinations for NIDDM: Glucovance (metformin/glyburide) Metaglip (glipizide/metformin) Avandamet (rosiglitazone/metformin) Actoplus Met (pioglitazonel/metformin)