Card Set Information

2011-09-04 15:01:07
PII Endocrinology IPAP

Anatomy & Physiology II: Endocrinology IPAP
Show Answers:

  1. What is paracrine action?
    When a hormone diffuses from one cell then acts on a nearby cell
  2. What is endocrine action?
    When a hormone acts on the same cell that released it
  3. What is autocrine action?
    When a hormone acts on the same cell that released it
  4. When deciding to give exogenous hormone therapy (i.e. synthetic thyroid hormone) what patient factors must be considered when prescribing the therapy?
    • 1. Kidney function
    • 2. Liver function
  5. What is the solubility characteristic of thyroid hormones and steroid hormones?
    They are lipid souble
  6. How are water-soluble hormones transported in the blood?
    In their free, unbound state
  7. How are lipid-soluble hormones transported in the blood?
    Attached to a carrier protein
  8. Explain why receptors for lipid-soluble hormones are located inside target cells.
    These hormones easily diffuse through the lipid bi-layer of target cell membranes so they are able to reach intracellular receptors
  9. Explain why receptors for water-soluble hormones are located within the plasma membrane of target cells.
    Water-soluble hormones cannot easily diffuse through the plasma membrane of target cells. The receptor has to be exposed on the cell surface in order for the hormone to bind to it.
  10. What is the major determinant of the extent/amplitude of hormone action on target cells?
    the number (or concentration) of available receptors
  11. What is up-regulation?
    When the number of receptors on target cells increases as the plasma concentration of a hormon decreases
  12. What is a first messenger?
    A water-soluble hormone bound to a surface receptor on a target cell
  13. What is/are the function(s) of second messengers?
    Second messengers are considered to be intracellular mediators of a hormone's action on target cells
  14. Which hormone class utilizes second messengers?
  15. Name the most common second messenger:
    cyclic AMP (cAMP)
  16. What are the 4 target cell activities taht phosphorylated enzymes regulate?
    • 1. intracellular enzymes
    • 2. protein synthesis
    • 3. cell secretions
    • 4. cell membrane permeability to other substances
  17. Negative feedback is:
    1. activating hormones are secreted in response to a LOW plasma concentration of a circulating hormone (the circulating hormone exerts effects at target cells).

    2. an increased plasma concentration of a circulating hormone exerts effects on hormone receptors located on the hypothalamus and pituitary gland. What effect does this have on synthesis and secretion of hormones? DECREASES

    3. A gradually decreasing plasma concentration of circulating hormone with time (as it is utilized by target cells) eventually INCREASES secretion of activating hormones by the hypothalamus and pituitary gland.
  18. Describe positive feedback
    The response to a secreted hormone (increased concentration in the blood) feeds back to the releasing organ causing continued or increased secretion of the hormone
  19. List 20 other mechanisms for regulating/controlling hormone secretion.
    • 1. Neural control
    • 2. Chemical control
  20. Name the endocrine organ that is the major link between the nervous system and the endocrine system
  21. The organ that regulates growth, development, metabolism, and overall body homeostasis by working with another endocrine organ (hypothalmus).
    Pituitary gland.
  22. What are the 5 releasing hormones?
    • 1. GHRH: Growth Hormone-Releasing Hormone
    • 2. TRH: Thyrotropin-Releasing Hormone
    • 3. PRH: Prolactin-Releasing Hormone
    • 4. CRH: Corticotropin-Releasing Hormone
    • 5. GnRH: Gonadotropin-Releasing Hormone
  23. The releasing hormones stimulate synthesis and release of hormones from which endocrine organ (specific)?
    Anterior Pituitary Gland
  24. What are the 2 inhibiting hormones?
    • 1. GHIH: Growth Hormone-Inhibiting Hormone
    • 2. PIH: Prolactin-Inhibiting Hormone
  25. What is another name for prolactin-inhibiting hormone?
  26. List 2 hormones that are synthesized in the hypothalamus and stored for later release from the posterior pituitary gland.
    • 1. ADH: Anti-Diuretic Hormone
    • 2. Oxytocin
  27. Describe ho hypothalamic releasing/inhibiting hormones are transported to the anterior pituitary gland.
    Hormones are released from vesicles at axon terminals near the base of the hypthalamus. They diffuse into the nearby primary capillary plexus. Blood flow carries the hormones to the secondary capillary plexus adjacent to the anterior pituitary gland. The hormones diffuse from the blood then attach to any available receptors on anterior pituitary target cells.
  28. What hormone does supraoptic nuclei synthesize?
    Anti-diurectic Hormone (ADH)
  29. What hormone does the paraventricular nuclei synthesize?
  30. Describe how oxytocin and ADH are transported from the hypothalamus to the posterior pituitary gland.
    They are packaged into secretory vesicles within the supraoptic and paraventricular nuclei. The secretory vesicles move down axons that extend from the hypothalamus into the posterior pituitary gland. The vesicles remain in the axon terminals within the posterior pituitary gland until needed.
  31. What is the stimulus for release of ADH and oxytocin?
    A neuroendocrine reflex
  32. The pituitary gland is connected to the underside of the hypothalamus by what structure?
  33. What is another name for the anterior pituitary gland?
  34. What are the 5 hormones synthesized and released by the anterior pituitary gland known as?
    Trophic hormones
  35. Breifly describe how trophic hormones enter the general blood circulation.
    Trophic hormones are released from anterior pituitary cells then they diffuse into the nearby secondary capillary plexus. The blood flow through the capillary plexus carries the hormones through the anterior hypophyseal veins into the general circulation.
  36. What are the 5 hormones synthesized by the anterior pituitary gland and the specific cell type involved.
    • 1. Human Growth Hormone (hGH): Somatotrophs
    • 2. Prolactin: Lactotrophs
    • 3. Adrenocorticotrophic hormone (ACTH): Corticotrophs
    • 4. Thyroid-Stimulating Hormone: Thyrotrophs
    • 5. Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH): Gonadotrophs
  37. Most metabolic effects of human growth hormone (hGH) are mediated by what substance(s)?
    Insulin-Like Growth Factors (IGFs)
  38. What are some locations where IGFs are produced?
    • 1. Liver
    • 2. Bone
    • 3. Muscle
    • 4. Cartilage
  39. What effect does hGH have on the plasma concentration of proteins?
    Increases them
  40. What effect does hGH have on the plasma concentration of glucose?
    Increases it
  41. What is the major regulator of hGH secretion?
    plasma glucose concentration
  42. When the plasma concentration of glucose is low, what effect doe this have on secretion of growth-hormone inhibiting (GHIH) and growth-hormone releasing hormone (GHRH)?
    • 1. GHIH: Decreases
    • 2. GHRH: Increases
  43. When GHIH decreases and GHRH increases, what does this do to hGH secretion?
    Increases it
  44. What effect(s) does stress and strenuous exercise have on hGH secretion?
  45. What effect do cortisol, insulin, glucagon, and estrogen secretion have on hGH secretion?
    Increases it
  46. What is the most common etiology of pathologic hypersecrtion of hGH?
    Benign Pituitary Adenoma
  47. Name the disease caused by hGH hypersecretion in adults.
  48. Name the disease caused by hGH hypersecretion in children.
  49. Chronically elevated plasma hGH exerts and adverse effect on pancreatic beta cells. What is this effect and what is the name of this effect?
    Beta cells eventually cease release of insulin. This is known as PITUITARY DIABETES.
  50. hGH hyposecretion in childhood causes what disorder?
  51. What is/are the primary function(s) of adrenocorticotrophic hormone (ACTH)?
    Regulates secretion of cortisol and other adrenocorticoids from the adrenal cortex.
  52. What is/are the primary function(s) of prolactin?
    Initiates milk synthesis and secretion
  53. Name the 2 hormones secreted by the hypothalamus that affect prolactin secretion
    • 1. PRH
    • 2. PIH (Dopamine)
  54. Describe how nursing affects dopamine and prolaction secretion.
    • 1. Dopamin secretion decreases
    • 2. Prolactin secretion increases
  55. What is the most common cause of hypersecretion?
    A benign pituitary adenoma (commonly known as prolactinoma)
  56. What type of patient should prolactinoma be a considered diagnosis?
    a non-pregnant, non-lactating female
  57. Follicle Stimulating Hormone (FSH) and lutenizing hormone (LH) secretion is stimulated by what hormone?
    Decreased circulating testosterone and estrogen
  58. What is another name for the posterior pituitary gland?
  59. The posterior pituitary gland is composed primarily of what type of tissue (specific)?
    Axons and axon terminals (nerve tissue)
  60. The quantity of ADH secreted by the posterior pituitary gland is in response to what two factors involving the blood circulation?
    • 1. Blood osmotic pressure (Plasma osmolarity)
    • 2. Blood volume
  61. List the 3 tissues that have receptors for ADH and describe the action of ADH at each of these tissues.
    • 1. Kidneys: increases water reabsorption by renal tubules
    • 2. Sweat glands: Decreases sweating
    • 3. Vascular smooth muscle: Causes vasoconstriction (especially during a significant hemorrhage)
  62. Release of atrial natiuretic peptide (ANP) has what effect on ADH secretion?
    it decreases
  63. Diabetes insipidus is a disease process caused by insufficient ADH acts on on target tissues. List 2 ways this can occur.
    • 1. Insufficient release of ADH from the posterior pituitary
    • 2. ADH receptor defect at the kidney tubules
  64. What is the most common cause of neurogenic diabetes insipidus?
    head trauma
  65. What are 2 primary symptoms associated with diabetes insipidus?
    • 1. polyuria
    • 2. polydipsia
  66. What are 2 primary functions of oxytocin?
    • 1. Stimulates milk ejection from the breasts
    • 2. Stimulates uterine contractions during labor
  67. Calcitonin (a hormone) is secreted by the thyroid gland. Name the cell type involved.
  68. Describe the anatomy of thyroid follicles
    Microscopic spherical sacs surrounded by follicular cells
  69. The lumen of thyroid follicles contains what substance?
  70. What is the primary protein contained in colloid?
  71. List the 2 hormones synthesized by thyroid follicles
    • 1. Thyroxine (T4)
    • 2. Triiodothyronine (T3)
  72. Which of the hormones (T3/T4) is secreted from the thyroid gland in the greatest quantity?
  73. Thyroid hormone synthesis requires an adequate amount of a specific dietary substance in the blood; name it.
  74. Name the amino acid within thyroglobulin structure that is important in thyroid hormone synthesis.
  75. One iodine + tyrosine = ?
    Monoiodotyrosine (MIT)
  76. Two iodines + tyrosine = ?
    Diiodotyrosine (DIT)
  77. Thyroxine = ?
    No MIT + Two DIT
  78. Triiodothyronine = ?
    One MIT + One DIT
  79. Once the 2 thyroid hormones are synthesized, they remain attached to what substance within the colloid?
  80. Name the hormone that stimulates secretion of T3 and T4 from thyroid follicles.
    Thyroid-Stimulating Hormone (TSH)
  81. In what state are T3 and T4 released into the blood?
    Free (Unbound)
  82. More than 99% of the T3 and T4 released into the blood are immediately bound to a carrier/transport protein; name it.
    Thyroxine-binding globulin
  83. Name the 2 activating hormones that regulate secretion of T3 and T4 from the thyroid gland.
    • 1. Thryotropin-releasing hormone
    • 2. Thyroid-stimulating hormone
  84. Increased concentration of circulating T3 and T4 affect secretion of the activating hormones; in what ways?
    Secretion of both TRH and TSH decreases
  85. A disease process that involves the thyroid gland directly (a primary thyroid disorder) and causes insufficient T3 and T4 secretion into the blood circulation. How does this affect TRH and TSH secretion?
    Secretion of both TRH and TSH increases
  86. Colloid normally contains a thyroid hormone reserve. Approximately how many months worth?
    2-3 months
  87. Several endogenous and exogenous factors affect TRH and TSH secretion. List 4 common ones:
    • 1. Low Basal Metabolic Rate
    • 2. Hypoglycemia
    • 3. Exposure to a cold environment
    • 4. Pregnancy
  88. TSH stimulates release of T3 and T4 from the thyroid gland. What other primary effect does it have on thyroid gland tissue?
    It stimulates follicular cell growth
  89. How does thryoid hormone increase the basal metabolic rate (BMR)?
    It's activity at target cells increases ATP formation and utilization
  90. Thyroid affects a specific cell membrane transport mechanism; name it.
    Na+ / K+ pumps
  91. What effect(s) does thryoid hormone have on protein synthesis, cellular uptake of glucose, and lipolysis?
    All are stimulated by T3 and T4
  92. What effect(s) does thyroid hormone have on beta adrenergic receptors on the heart and peripheral nerves?
    they are up-regulated
  93. What effect(s) does thyroid hormone have on secretion of human growth hormone?
    It increases
  94. What are the 2 primary causes of hypothyroidism?
    • 1. A primary thyroid disorder - usually due to an autoimmune process
    • 2. Inadequate secretion of TSH from the anterior pituitary gland
  95. What is myxedema?
    Sever hypothyroidism seen in adults
  96. Is hypothyroidism a common cause of obesity?
    No... Any weight gain associated with hypothyroidism is modest (Avg is 10-30 lbs.)
  97. Describe endemic goiter.
    An enlargement of the thyroid gland that may be symmetric or asymmetric
  98. List the causes of endemic goiter
    • 1. Most common: Dietary iodine deficiency
    • 2. Inability to utilize iodide to synthesize T3 and T4
  99. What is the pathophysiology of endemic goiter (specific)?
    Thyroid gland enlargement occurs as a result of TSH hypersecretion. TSH stimulates follicular cell growth.
  100. Describe the pathophysiology of Graves' disease.
    An autoimmune disorder caused by production of an autoantibody (Thyroid-stimulating Immunoglobulin) that mimics TSH at Receptors. Pathologically increased amounts of T3 and T4 are synthesized and released into the blood circulation
  101. Pathologically increased concentrations of circulating T4 and T3 affect the eyes in some patients with Graves' disease; how?
    Retro-orbital edema causes protrusion of the eyes. The edema occurs in the extra-ocular muscles
  102. Many symptoms and signs of Graves' disease are due to thyroid hormone effects on tissues such as the heart and nervous system. What is happening to target tissue receptors for T3 and T4 that cause these signs and symptoms?
    Up-regulation of beta adrenergic receptors
  103. Normal regulation of circulating calcium is important for the proper function of some physiologic processes. List the 3 mentioned in lecture.
    • 1. Nerve impulse initiation, propagation, and synaptic vesicle release
    • 2. Muscle action potentials
    • 3. Blood coagulation
  104. What are the 3 factors that affect bone breakdown and bone formation?
    • 1. Ratio of osteoblast to osteoclast activity
    • 2. Intestinal absorption of calcium and phosphate
    • 3. Urinary excretion of calcium and phosphate
  105. What are the 3 major hormones involved in calcium homeostasis and the role of each?
    • 1. Parathyroid hormone (PTH): Increases blood calcium and decreases phosphate
    • 2. Calcitonin: Decreases blood calcium and phosphate
    • 3. Calcitrol: Increases blood calcium and phosphate concentration
  106. Describe the location of the parathyroid glands
    They are embedded in the posterior aspect of the thyroid gland - 2 in each lobe
  107. What cell type within the parathyroid glands is responsible for synthesis of parathyroid hormone (PTH)?
    Principal (Chief) cells
  108. Where is calcitonin synthesized?
    In parafollicular "C" cells in the thyroid gland.
  109. What are the 3 mechanisms by which PTH increases the plasma calcium concentration?
    • 1. Increases osteoclast activity releasing calcium into the blood
    • 2. Increases renal tubular reabsorption of calcium
    • 3. Stimulates renal synthesis of calcitrol (Vitamin D)
  110. What is the primary stimulus for secretion of PTH?
    Decreased plasma calcium concentration
  111. What are 2 mechanisms by which calcitonin decreases the plasma concentration?
    • 1. Inhibits formation and activity of osteoclasts
    • 2. Decreases renal tubular reabsorption of calcium
  112. Is calcitonin an important hormone in the adult? Why or why not?
    No. After skeletal maturity there is much less bone formation and remodeling
  113. What are 2 other names for 1,25-dihydroxycholecalciferol?
    • 1. Calcitrol
    • 2. Vitamin D
  114. What are the 3 organs responsible for synthesis of 1,25 dihydroxycholecalciferol?
    • 1. Skin
    • 2. Liver
    • 3. Kidneys
  115. What organ of the three (skin, liver, kidneys) requires another hormone for synthesis of 1,25 dihydroxycholecalciferol?
    PTH (In the kidneys)
  116. What is the primary hormonal effect of calcitrol (specific)?
    Increases absorption of calcium from the small intestine
  117. What effect does a specific protein have on intestinal absorptive cells and what is that specific protein?
    The activity of calcium-binding protein enhances calcium transport into absorptive cells
  118. What effects does hypoparathyroidism have on PTH secretion and plasma calcium concentration?
    PTH secretion decreases and the plasma calcium concentration decreases
  119. Name a dangerous complication of hypoparathyroidism.
    Muscle tetany
  120. Hypocalcemia may be a complication of what surgical procedure(s)?
    • 1. Parathyroidectomy
    • 2. Total thyroidectomy (inadvertent removal of the parathyroid glands)
  121. How is hypocalcemia treated?
    Very small piece of the patient's preserved parathyroid tissue is implanted under the skin of the forearm. It rapidly begins secreting PTH.
  122. What effects does hyperparathyroidism have on PTH secretion and plasma calcium concentration?
    • 1. PTH secretion increases
    • 2. The plasma calcium concentration increases
  123. Where is most of the plasma calcium coming from in hyperparathyroidism?
    The bones
  124. Describe rickets
    Deformed bones of the lower extremities usually seen in children caused by Vitamin D deficiency
  125. What specifically is causes hypertrophy of the parathryoid glands?
    Hypersecretion of PTH
  126. What effect(s) does rickets have on bone mineralization?
    It is decreased
  127. What is osteomalacia?
    Softening of bone in adults not commonly associated with low dietary Vitamin D intake
  128. What are 5 common causes of osteoporosis?
    • 1. Old age
    • 2. Malnutrition
    • 3. Decreased secretion of estrogen and testosterone
    • 4. Lack of exercise/ambulation
    • 5. Cushing's syndrome
  129. Briefly describe the pathophysiology of Paget's disease of the bone.
    Abnormally increased osteoclast activity on bone not associated with PTH hypersecretion
  130. The adrenal medulla is composed of what cell type?
  131. What are the 3 zones of the adrenal cortex and the primary substance produced by each?
    • 1. Zona Glomerulosa: Mineralcorticoids
    • 2. Zona Fasiculata: Glucocorticoids
    • 3. Zone Reticularis: Gonadocorticoids
  132. Aldosterone regulates the plasma concentration of what 2 electrolytes?
    • 1. Sodium
    • 2. Potassium
  133. What are 2 stimuli for aldosterone secretion?
    • 1. Increased formation angiotensin II (when blood pressure is low)
    • 2. Increased plasma potassium concentration
  134. What is the primary electrolyte abnormality associated with Conn's (Chron's?) disease?
    Hypokalemia (may also see hypernatremia)
  135. What are the 3 major glucocorticoids?
    • 1. Cortisol
    • 2. Cortisone
    • 3. Corticosterone
  136. Which of the 3 major gluccocorticoids is secreted in the greates quantity and has the greatest metabolic activity?
  137. What effect does cortisol have on plasma glucose?
    It increases
  138. Why is cortisol known as the "stress hormone?"
    It increases resistance to stress by facilitating an increase in blood pressure and by increasing the plasma glucose concentration
  139. What effect does cortisol have on inflammation?
    It suppresses inflammation
  140. Why are exogenous glucocorticoids prescribed for patients who have received an organ transplant?
    They suppress the immune system. This decreases the risk of organ rejection
  141. How does cortisol affect tissue healing?
    It slows wound healing/tissue repair
  142. What effect does cortisol have on bone?
    Increased protein catabolism causes loss of organic bone matrix
  143. Normally, cortisol secretion is regulated by negative feedback. Is this true in high stress situations (i.e. trauma, major surgery, acute anxiety)? Why or why not?
    No. Patients experiencing highly stressful situations will increase their secretion of CRH overriding negative feedback inhibition
  144. What effect does decreased plasma cortisol have on CRH and ACTH secretion?
    Secretion of both increases
  145. Patient's with Addison's disease hyposecrete 2 hormones; name them:
    • 1. Cortisol
    • 2. Aldosterone
  146. What is the most common cause of Addison's disease?
    An autoimmune process that causes atrophy of the adrenal glands
  147. What is another name for Addison's disease?
    Primary Adrenocorticoid Insufficiency
  148. Several signs and symptoms are associated with the cortisol abnormality in Addison's disease. Which of them must be identified early and treatment provided to patients who have suffered major trauma, who are experiencing a serious illness, or who are being prepped for major surgery?
    The patient cannot respond to high stress situations by secreting cortisol. Patients with Addison's disease should wear a medical ID bracelet so medical personnel will administer exogenous glucocorticoids
  149. Patient's with Addison's disease exhibit abnormal plasma concentrations of Na+ and K+. Identify which electrolyte is increased and which is decreased.
    • 1. Potassium: Increased
    • 2. Sodium: Decreased
  150. Patients with Addison's disease hypersecrete 2 hormones from the pituitary gland. Name them.
    • 1. ACTH
    • 2. MSH
  151. Which of the hormones hypersecreted in Addison's disease affects the skin and what is a physical sign of Addison along with the reason it occurs?
    Diffuse skin bronzing due to the increased secretion of MSH
  152. What is the most common cause of pathologic cortisol hypersecretion?
    ACTH hypersecretion by a pituitary tumor
  153. What is another less common cause of pathologic hypersecrtion other than a pituitary tumor?
    An adrenal adenoma
  154. Ordering a lab test to check the plasma concentration of which hormone will be most helpful in distinguishing which endocrine organ is diseased?
  155. What will the plasma concentration of glucose be in patients with a pituitary tumor or adrenal adenoma?
    Plasma glucose levels will be increased.
  156. Increased protein catabolism in patients with cortisol hypersecretion affects the muscles. What clinical sign is associated with this?
    Muscle Atrophy (Wasting)
  157. Is Dihydroepiandrosterone (DHEA) known as a weak or strong androgen?
  158. Is DHEA a necessary androgen in the adult male? Why or why not?
    No, the effects of testosterone predominate
  159. What is important about DHEA secretion in the post-menopausal female?
    DHEA is the only remaining source of estrogen
  160. DHEA and other weak androgens are important in growth and development of children. The effects of DHEA are most prominent in what stage child growth and development?
  161. What are the 3 catecholamines secreted from the adrenal medulla?
    • 1. Epinephrine
    • 2. Norepinephrine
    • 3. Dopamine
  162. Why is epinephrine secreted in the greatest quantity from the adrenal medulla?
    During stress, increased cortisol secretion activates an enzyme in chromaffin cells that converts most norepinephrine to epinephrine prior to release into the blood
  163. Prolonged mass sympathetic discharge ("fight or flight") may be necessary in some situations. Why is adrenal secretion of epinephrine and norepinephrine important in these situations?
    Their hormonal activity lasts 5-10 times longer than the epinephrine and norepinephrine secreted from sympathetic nerve endings
  164. What effects does epinephrine have on cardiac output and blood pressure?
    they both increase
  165. What effect does norepinephrine have on systemic vascular system?
    It causes vasoconstriction
  166. Describe a pheochromocytoma.
    A tumore that forms in chromaffin cells and hypersecretes epinephrine and norepinephrine
  167. True or False: Pheochromocytomas are only found in the adrenal gland.
  168. Patients with pheochromocytoma often have hypertension. Describe how this secondary cause for hypertension is different than cases of essential hypertension commonly seen in the clinic.
    This type of hypertension is very difficult to control. It is common to see random blood pressure spikes.
  169. Where is the most common location for a pheochromocytoma outside of the adrenal medulla?
    Small para-aortic bodies
  170. What are para-aortic body tissues known as?
    Organs of Zuckerkandl
  171. What are the 2 primary cell types that comprise the pancreas?
    • 1. Acinar
    • 2. Islets of Langerhans
  172. What type of cells within the pancreas secretes endocrin hormones?
    Islets of Langerhans
  173. What are the 4 islet cell types and the primary hormone secreted by each?
    • 1. Alpha cells: Glucagon
    • 2. Beta cells: Insulin
    • 3. Delta cells: Somatostatin
    • 4. F Cells: Pancreatic polypeptide
  174. What is the function of glucagon?
    Increases blood glucose when it is too low.
  175. What are two physiolgic process that occur in relation to glucagon?
    • 1. Glycogenolysis
    • 2. Gluconeogenesis
  176. Glucagon action can increase the plasma concentration of non-glucose energy sources for tissue cells. What are 2 physiologic process that occur?
    • 1. lipolysis
    • 2. ketogenesis
  177. Why is adequate glucagon secretion important for the brain?
    Glucose is the desired energy source for the brain
  178. The circulating concentration of what hormone regulates glucagon secretion?
  179. Name another stimulus for glucagon seceretion other than concentration of insulin.
    Increased sympathetic nervous system activity
  180. What is the function of insulin?
    Decreases blood glucose when it is too high.
  181. What effect does insulin have on glycogenolysis and gluconeogenesis?
    Both processes are inhibited
  182. The circulating concentration of what hormone regulates insulin secretion?
  183. What are 2 other major stimulin for insulin secretion other than concentration of glucagon?
    • 1. Parasympathetic vagal stimulation of the pancreas
    • 2. Secretion of glucose-dependent insulinotropic peptide (GIP)
  184. What two hormones exhibit a synergistic effect that is essential for growth and development?
    • 1. Insulin
    • 2. Human Growth Hormone (hGH)
  185. What are the 3 "Ps" of diabetes mellitus?
    • 1. Polyuria
    • 2. Polydipsia
    • 3. Polyphagia (Type I)
  186. What is the pathophysiology of type I diabetes mellitus?
    Pancreatic beta cells degenerate and do not secrete insulin
  187. What treatment is required for patients with type I diabetes mellitus?
    Insulin replacement therapy
  188. What is the pathophysiology of type II diabetes mellitus?
    Insulin receptor insensitivity to insulin at target cells
  189. Patients in early phase of type II diabetes mellitus have an increased plasma concentration of which pancreatic hormone?
  190. Do patients with type II diabetes mellitus require insulin replacement therapy?
    Some patients do eventually require insulin replacemnt (approximately 50%)
  191. Obese patients are more likely to develop type II diabetes mellitus. Why?
    Research indicates that there are fewer insulin receptors in obese persons. Add this to insulin receptor insensitivity to insulin and it is obvious that the risk of developing type II diabetes mellitus increases
  192. Diabetic patients who inject too much insulin can develop hypoglycemia. What are some common signs and symptoms that diabetic patients who inject insulin must be aware of?
    • 1. Weakness
    • 2. Tremors
    • 3. Sweating
    • 4. Disorientation (noted by others)
  193. All diabetic patients who inject insulin should have a readily availble source of injectable _____________.
  194. Describe insulinoma.
    An adenoma that develops in an islet of langerhans that hypersecretes insulin
  195. In what type of patient should providers consider insulinoma?
    A healthy patient who has repeated episodes of hypoglycemia
  196. What is the primary cause of diabetic ketoacidosis (DKA)?
    Insulin deficiency: Either endogenous insulin hypersecretion or failure to administer exogenous insulin if a diabetic
  197. Increased formation of plasma ketones in patients with DKA is often noticeable; in what way?
    Patients often have a sweet breath odor
  198. Patients with DKA have what type of acidosis?
  199. What is the compensatory response to metabolic acidosis that is often observed in patients with DKA?
    Increased rate and depth of breathing.
  200. Where is the pineal gland located?
    It's part of the epithalamus
  201. Name the hormone synthesized by the pineal gland.
  202. What effect does melatonin have on sleep?
    Promotes sleep
  203. Where is the thymus located?
    Within the mediastinum anterior to the aorta and posterior to the manubrium
  204. What are the 4 thymic hormones?
    • 1. Thymosin
    • 2. Thymopoetin
    • 3. Thymic humoral factor
    • 4. Thymic Factor
  205. What is the activity of all of the thymic hormones?
    They stimulate T-Cell differentiation into killer, helper, or suppressor cells
  206. What types of cells does the Thymus produce that are involved in cell-mediated immunity?