1. Bio217: Pathophysiology Class Notes Professor Linda Falkow
Bio217 Fall2013
Unit 5
Bio217: Pathophysiology Class Notes Professor Linda Falkow
Unit V: Endocrine System Disorders
Chap. 17: Mechanisms of Hormonal Regulation
Chap. 18: Alterations of Hormonal Regulation

2. Mechanisms of Hormonal Regulation
Bio217 Fall2013
Unit 5
Mechanisms of Hormonal Regulation
Chapter 17

3. The Endocrine System Components Functions
Bio217 Fall2013
Unit 5
The Endocrine System
Components
Glands located around the body that secrete chemical messengers (_________)
Functions
Works with _______to regulate and integrate metabolism and maintain homeostasis
Functions: Stimulation of growth and development
Coordination of the male and female reproductive system
Maintenance of internal environment
Adaptation to emergency demands of body

4. Hypothalamus (“heart of the endocrine system”)
Bio217 Fall2013
Unit 5
Hypothalamus (“heart of the endocrine system”)
Center for integrating endocrine and ANS
Regulates endocrine glands via
_________and ___________ pathways
Posterior Pituitary Anterior Pituitary
(neural pathways) (hormonal control)
ADH (antidiuretic hormone) ACTH (adrenocorticotropic horm.)
Oxytocin TSH (thyroid stim. hormone) LH (luteinizing hormone)
FSH (follicle stim. hormone)
also GH (growth horm.)
and PRL (prolactin)
ADH- causes water retention
Oxytocin – stimulates uterine contractions during labor and milk secretion in lactating women

5. Negative Feedback- regulates the endocrine system by ________________ overproduction of hormones

6. Lipid-Soluble Hormones

7. Hormone Binding at Target Cell

8. Anterior Pituitary Hormones

9. Endocrine disorders May be caused by
Bio217 Fall2013
Unit 5
Endocrine disorders
May be caused by
Hypersecretion or hyposecretion of hormones
Hyporesponsiveness of hormone receptors
Gland inflammation
Tumors of glands
Hyper or hyposecretion may be in the hypothalamus or pituitary or target glands
Hypersecretion  elevated levels
Hyposecretion  decreased levels of hormones

10. Adrenal glands Embedded in fat superior to each kidney Adrenal cortex:
1. Aldosterone (_________________)
– regulates Na+ reabsorption & excretion of K+
2. Cortisol (______________)
- stimulates gluconeogenesis
- protein breakdown and fatty acid mobilization
-suppression of immune system
- increased stress response
- maintains BP and CV fcn.
3. Adrenal androgens & estrogens (_______________)

11. Aldosterone

12. Adrenal medulla Epinephrine & Norepinephrine (catecholemines)
Bio217 Fall2013
Unit 5
Adrenal medulla
Epinephrine & Norepinephrine (catecholemines)
- produce VC
- _______ response (“fight or flight”)
Epi = adrenalin
Nepi = noradrenalin
Release of catecholamines has been characterized as a “fight or flight” response
Catecholamines promote hyperglycemia

13. Catecholamines

14. Thyroid and Parathyroid Glands
Bio217 Fall2013
Unit 5
Thyroid and Parathyroid Glands
Thyroid gland
Located in anterior neck ; two lobes lie on either side of the trachea
Secrete Iodine – containing hormones
____________ – nec. for growth & dev.; increase metabolism
____________ – regulates blood Ca++ levels
Parathyroid glands
4 glands located on posterior aspect of thyroid
Secrete _________
Regulates blood Ca++ levels
90% T4 and 10% T3
Calcitonin decreases blood Ca++
PTH increases blood Ca++

15. Thyroid and Parathyroid Glands

16. Endocrine Pancreas The pancreas is both an __________ and
Bio217 Fall2013
Unit 5
Endocrine Pancreas
The pancreas is both an __________ and
_________ gland
Contains pancreatic islets (of Langerhans)
Secretion of glucagon and insulin
Cells
Alpha—glucagon ( nec. when fasting _________ BG)
Beta—insulin (released after a meal  _________BG,
stim. protein syn. and fatty acid uptake & storage)
Delta—somatostatin and gastrin
F cells—pancreatic polypeptide

17. Endocrine Pancreas

18. Bio217 Fall2013
Unit 5
Concept Check
1. Organs that respond to a particular hormone are called:
A. target organs C. responder organs
B. integrated organs D. hormone attach organs
2. The hypothalamus controls the anterior pituitary by:
A. Nerve impulses C. Regulating hormones
B. PG D. None of the above
1. A 2. C

19. B. TSH D. All of the above are regulatory for thyroid homone secretion
Bio217 Fall2013
Unit 5
3. In a negative feedback mechanism controlling thyroid hormone secretion, which is the nonregulatory hormone?
A. TRH C. thyroxine
B. TSH D. All of the above are regulatory for
thyroid homone secretion
Matching:
____ 4. ACTH a. Mammary glands
____ 5. TSH b. Adrenal cortex
____ 6. TRF c. Thyroid gland
____ 7. prolactin d. Ant. pit.
Matching: a. Influence inflam. response
___ 8. Epi b. Causes fight or flight response
___ 9. Glucocorticoids c. Controls Na+, H+, K+
___ 10. Mineralcorticoids d. Act as minor sex hormones
___ 11. Gonadocorticoids
C 4. b c d 7. a
B 9. a 10. c 11. d

22. Alterations of Hormonal Regulation
Chapter 18

23. Elevated or Depressed Hormone Levels
Failure of feedback systems
Dysfunction of an endocrine gland
Secretory cells are unable to produce, obtain, or convert hormone precursors
The endocrine gland synthesizes or releases excessive amounts of hormone
 abnormal hormone levels

24. Endocrine Disorders
Pituitary disorder of water metabolism (diabetes insipidus)
3 Thyroid gland disorders (goiter, hyperthyroidism, hypothyroidism)
Pancreatic disorder (diabetes mellitus: type 1 and type 2)
2 Adrenal disorders (Addisons’s and Cushing’s syndrome)

25. Elevated or Depressed Hormone Levels
Increased hormone degradation or inactivation
Ectopic hormone release

26. Diseases of the Posterior Pituitary
Bio217 Fall2013
Unit 5
Diseases of the Posterior Pituitary
Diabetes insipidus
Deficiency of _________ (aka vasopressin)
Polyuria (4-16 L/day) and polydipsia
Partial or total inability to concentrate urine
Causes: drugs or injury to posterior pituitary; lesions in hypothalamus, infundibulum or post. pit.
Normally ADH is syn. in hypothalamus and stored in post. pit. ADH is released when plasma osmolality increases  increased permeability to dct and cd in kidney  increased reabsorption of water.
When ADH is missing: results in increased excretion of water  large amt. of dilute urine
Other causes: brain tumor, removal of pit. gland, aneurysm, thrombus, immunologic disorder, or infection

27. Diabetes Insipidus Pathophysiology: Treatment: replacement of ADH
Patients not able to concentrate urine
Deficiency of ADH  ___________ vol. of dilute urine
 ____________ if fluids are not replaced
Treatment: replacement of ADH

28. Alterations of Thyroid Function
Bio217 Fall2013
Unit 5
Alterations of Thyroid Function
Goiter = enlargement of thyroid gland
not due to inflammation or neoplasm
Classified as:
nontoxic (increased demand for TH during adolescence, pregnancy or menopause) and
toxic (due to long term nontoxic, occurs in elderly)
Please pass the iodine
Endemic goiter due to insufficient dietary iodine  insufficient production of TH
Too much of a good thing
Sporadic goiter due to ingestion of goitrogenic foods* ( inhibit thyroxine) or drugs
Goiter belts- areas of Midwest, NW, and Great Lakes where high incidence of endemic goiter occurs (I- deficient soil and water)
Goitogenic foods = rutabegas, cabbage, cabbage, soybeans, pnuts, peaches, peas, strawberries, spinach, radishes
Goitrogenic drugs – propylthiouracil, iodides, aminosalicylic acid, cobalt, lithium

29. Goiter Pathophysiology
Decreased iodine plus impaired synthesis of TH  responsiveness of thyroid to TSH
Increased mass and cell activity may overcome mild thyroid impairment (Patient has goiter but normal fcn.)
If severe impairment  goiter and hypothyroidism

30. Alterations of Thyroid Function
Hyperthyroidism

31. Hyperthyroidism or thyrotoxicosis (Graves Disease)

32. Graves’ Disease How grave is Graves’ disease?
Graves’ disease is most common type
Autoimmune, years old, family history of thyroid abnormalities
Thyroid-stimulating antibodies bind to TSH receptors
Thyroid storm (thyrotoxic crisis)
Overproduction of T3 and T4  increased SNS activity
( tachycardia, vascular collapse, hypotension, coma, death)

33. Graves’ disease Signs & Symptoms Enlarged thyroid
Bio217 Fall2013
Unit 5
Graves’ disease
Signs & Symptoms
Enlarged thyroid
Exophthalmos (_______________)
Nervousness, weight loss w/ increased appetite
Treatment
Antithyroid drugs (propylthiouracil, methimazole)
131 I (radioactive iodine therapy)
Surgery
Lab tests for increased T3 and T4; TSH is low in primary hyperthyroidism, but high when excess TSH is cause; thyroid scan

34. Alterations of Thyroid Function
Bio217 Fall2013
Unit 5
Alterations of Thyroid Function
Hypothyroidism
Thyroid deficiency (decreased T3 and T4)  metabolic processes slow (may be problem with thyroid, pituitary, or hypothalamus)
Primary hypothyroidism – due to disorder of thryoid
Secondary hypothyroidism –due to failure to stimulate thyroid
Causes: thyroidectomy, radiation, not enough TSH (from pituitary) or TRH (from hypothalamus)
Symptoms: fatigue, wt. gain, facial puffiness, dry skin, bleeding tendencies
TRH = thyroid stimulating releasing hormone

35. Pathophysiology
Loss of thyroid tissue  decreased TH, increased TSH and goiter (primary)
Decreased TSH from pituitary most commonly due to tumors (secondary)
Myxedema- composition of dermis is changed (puffiness)
Myxedema coma - depressed respiratory system , decreased cardiac output, bradycardia & hypotension
Treatment: TH replacement gradually (levothyroxine)

36. Hypothyroidism

37. Diabetes Mellitus Body does not produce or use _________ properly
Results in hyperglycemia
Type 1 (IDDM = insulin-dependent)
Type 2 (NIDDM = non-insulin-dependent)

38. Type 1 diabetes Pathophysiology (Type 1) Symptoms
Islet cell (beta cell) destruction  no insulin production
Autoimmune (genetic & environmental)
Nonautoimmune (idiopathic)
Symptoms
Lack of insulin ______________ occurs w/ 89-90% destruction of beta cells; excess glucagon by alpha cells
Glucosuria, polyuria, polydipsia
Ketoacidosis due to fat and protein metabolism  DKA coma
Treatment: Insulin, meal planning and exercise, Hb A1C

39. Type 2 diabetes mellitus
Pathophysiology
Idopathic, genetic and environmental factors
Insulin resistance in target tissues
Overproduction of glucose via gluconeogenesis
Obesity
Symptoms
Recurring skin infections
Visual changes (blurred vision, retinopathy)
Paresthesias
Fatigue (poor eating)
Treatment
Personalized meal plan & exercise

40. Acute Complications of Diabetes Mellitus
Hypoglycemia (insulin shock- decr. BG levels)
Diabetic ketoacidosis _______ – dec. insulin levels elevated BG levels  fat mobilized
Somogyi effect – hypoglycemia followed by hyperglycemia (rebound)
Dawn phenomenon – early morning elevated BG

41. Diabetic Ketoacidosis

42. Chronic Complications of Diabetes Mellitus
Hyperglycemia
Microvascular disease
Retinopathy
Diabetic nephropathy
Macrovascular disease
Coronary artery disease
Stroke
Peripheral arterial disease
Diabetic neuropathies
Infection

43. Alterations of Adrenal Function
Bio217 Fall2013
Unit 5
Alterations of Adrenal Function
Disorders of the adrenal cortex
Cushing disease
Excessive anterior pituitary secretion of ________
Cushing syndrome
Cluster of abnormalities due to excessive levels of cortisol (glucocorticoid)
Wt. gain, muscle weakness, fatigue, buffalo hump, thin extremities, bruise easily
Treatment:
Radiation, drugs, surgery depending on cause

44. Cushing Disease
Before onset of Cushing syndrome
4 months later

45. Addison’s disease (adrenal insufficiency or hypofunction)
____________ mineralcorticoid, glucocorticoid, and androgen secretion
Cause – usually from autoimmune process
Idiopathic, TB, removal of adrenals, neoplasms, infections
Adrenal crisis
Inadequate or nonresponsive hormone therapy
Extreme stress
 hypoglycemia, hypotension  coma  death

46. Bio217 Fall2013
Unit 5
Concept Check
1. Which clinical symptoms are shared by DM and diabetes inspidus?
A. Elevated blood and urine glucose levels
B. Inability to produce ADH
C. Inability to produce insulin
D. Polyuria
2. Graves disease is:
A. Hyperthyroidism
B. Associated with autoimmunity
C. Characterized by ophthalmopathy
D. All of the above
1. D 2. D

47. Bio217 Fall2013
Unit 5
3. A 24-year old female with a history of “juvenile onset” diabetes is found in a stupor. She has cold, clammy skin, what is most likely the cause of her condition?
A. Hyperglycemia
B. Insulin shock
C. Renal failure
D. retinopathy
4. Common signs and symptoms of DM include all of the following except:
B. Blurred vision
C. Increased muscle anabolism
D. polyuria
3. B 4. C

48. Matching: ___ 5. Cushing disease A. Excess cortisol
Bio217 Fall2013
Unit 5
Matching:
___ 5. Cushing disease A. Excess cortisol
___ 6. Goiter B. Enlarged thyroid
___ 7. Addison disease C. Adrenal hypofunction
5. A 6. B 7. C