Anatomy and Physiology of the Endocrine System, Thyroid Disorders and Diseases, Diabetes, Hyperglycemia, Hypoglycemia, Obesity

1. Endocrine
Pathophysiology

2. Functions of the Endocrine System
• Collection of glands that produce hormones to:
Regulate metabolism
Regulate growth and development
Regulate tissue function
Regulate sexual function
Regulate reproduction
Regulate sleep
Regulate mood

3. Anatomy of the Endocrine System
• Pituitary Gland
 Master gland of the endocrine system
 Produces critical hormones
Anterior Lobe
 Releases hormones upon receiving releasing/inhibiting
hormones from the hypothalamus
Posterior Lobe
 Contains the ends of nerve cells from the
hypothalamus
 Hypothalamus sends hormones directly to the posterior
lobe via these nerves and then the pituitary gland
releases them

4. Anatomy of the Endocrine System
• Hypothalamus
 Part of the brain that links the endocrine
system to the nervous system
 Controls the pituitary gland

6. Anatomy of the Endocrine System
• Parathyroid Glands
 Four tiny glands located in the neck
 Control body’s calcium levels
 Produce parahormone
• Thyroid
 Gland found in the neck
 Regulates rate of metabolism
 Produces thyroxine

8. Anatomy of the Endocrine System
• Adrenal Glands
 One pair of ductless glands
located above the kidneys
 Adrenal Cortex produces
steroidal hormones
 Adrenal Medulla produces
epinephrine and
norepinephrine

9. Anatomy of the Endocrine System
• Pancreas
 Located partially behind the stomach and the
abdomen
 Functions as both an endocrine and exocrine
gland
 Produces digestive enzymes
 Produces insulin and glucagon

10. Anatomy of the Endocrine System
• Pineal Gland
 Small mass of tissue
near the brain
 Secretes melatonin

11. Anatomy of the Endocrine System
• Thymus Gland
 Gland located near
the heart
 Aid’s in the body’s
defense against
infection by making
antibodies

12. Anatomy of the Endocrine System
• Ovaries in females
Secrete estrogen and progesterone,
hormones that are vital to normal
reproductive development and fertility
• Testicles in males
Secrete testosterone, a hormone that is vital
to the normal development of male
characteristics

13. Endocrine Hormones
• Hormones are the chemical messengers of the
endocrine system that are released into the blood
• Protein Hormones
Class of hormones that cannot pass through the cell
membrane
Less likely to be stored in the body
• Steroid Hormones
Class of hormones that can pass through the cell
membrane
Can be stored in the body

14. Endocrine Hormones
• Prostaglandins
 Local hormones that do not enter the
bloodstream
• Growth Hormone
 Secreted by anterior pituitary gland
 Stimulates bone growth
• Luteinizing Hormone
 Protein hormone secreted by anterior pituitary
gland
 Stimulates ovulation in females and androgen
production in males

15. Endocrine Hormones
• Prolactin
Peptide hormone released by anterior pituitary
Promotes lactation
• Follicle-Stimulating Hormone
Secreted in increasing amounts during puberty
by the anterior pituitary
Stimulates development of reproductive cell
follicles

16. Endocrine Hormones
• Adrenocorticotropic Hormone
 Peptide hormone released from anterior
pituitary
 Stimulates production and secretion of steroid
hormones by adrenal cortex
• Oxytocin
 Produced by the hypothalamus and released
from posterior pituitary
 Induces contractions of uterine muscles during
labor

17. Endocrine Hormones
• Antidiuretic Hormone
 Secreted by posterior pituitary
 Aids in water reabsorption by the kidney
• Calcitonin
 Produced by thyroid gland
 Decreases blood calcium levels by stimulating
calcium deposit in the bones
 Antagonist of parathyroid hormone
• Parahormone
 Secreted by parathyroid glands
 Controls calcium and phosphate metabolism

18. Endocrine Hormones
• Cortisol
 Secreted from adrenal cortex
 Aids the body during stress
 Regulates glucose, carbohydrate, and fat levels
• Aldosterone
 Corticosteroid hormone secreted by adrenal cortex
 Regulates mineral balance in blood
 Controls fluid volume

19. Endocrine Hormones
• Insulin
 Hormone secreted by the beta cells of the
pancreas
 Responsible for regulating the metabolism of
glucose
• Glucagon
 Hormone secreted by the alpha cells of the
pancreas
 Raises blood glucose levels

20. Endocrine Hormones
• Estrogen
 General term for female steroid sex hormones
 Secreted by the ovary
 Responsible for typical female sexual
characteristics
• Progesterone
 Hormone produced by the ovaries
 Acts with estrogen to bring about the menstrual
cycle

21. Endocrine Hormones
• Testosterone
 Male sex hormone produced by the testes
 Promotes maturation of the reproductive system
accessory structures
 Promotes development of the male secondary sex
characteristics
• Melatonin
 Hormone secreted by the pineal gland
 Used to regulate sleep patterns

22. Classification of Hormones
• Anterior Pituitary Gland
Adrenocorticotrophic Hormone (ACTH)
Thyroid-Stimulating Hormone (TSH)
Luteinizing Hormone (LH)
Follicle-Stimulating Hormone (FSH)
Growth Hormone (GH)
Melanocyte-stimulating hormone (MSH)

23. Classification of Hormones
• Posterior Pituitary Gland
Anti-diuretic Hormone (ADH)
Oxytocin

24. Hormone Regulation
• Nervous System Signals
• Chemical Changes in the Blood
• Hormones regulate other hormones

25. Gigantism
• Acromegaly
• Thicker skull and jaw
• Occurs after joint plates fuse

26. Hyperthyroidism
• Common Cause: Graves
Disease
• Common Symptoms:
exopthalamos, goiter,
heat intolerance, and
anxiety

27. Hypothyroidism
• Very familial; 4 times more likely in
women
• Common Symptoms: weight gain, cold
intolerance, and fatigue
• Myxedema
Fluid buildup that does not pit
Can look like fibromyalgia because of
muscle aches and trigger point
tenderness
Sparse hair, brittle nails, Buffalo
hump

28. Thyroid Storm
• T3 and T4 are dumped into the system
• Causes tachycardia, fever, and agitation
• Life-threatening condition associated
with untreated or undertreated
hyperthyroidism

29. Thyroid Cancer
• Very treatable
• Most are benign – only 5%
are malignant and most do
not metastasize
• Palpation will be painless,
unilateral, and in one spot

30. Parathyroid Cancer
• Cannot be easily distinguished from thyroid
cancer
• Weakness, feeling tired, lump in the neck

31. Addison’s Disease
• HYPOADRENAL
autoimmune disease
• Skin changes color to a
slight grey

32. Cushing’s Syndrome
• HYPERADRENAL
• Too much glucocorticoids in the system
• Can cause muscle wasting, bone
demineralization, and ligament laxity

33. Diabetes
• Fasting plasma glucose >126 mg/dL
• Insulin makes glucose transporters closer to
the cell
• Three types:
Type 1
Type 2
Gestational

34. Type 1 Diabetes
• Autoimmune; typically presents in under
age 20
• Insulin produces B-cell destruction
• Risk Factors: sibling or parents have type 1

36. Type 2 Diabetes
• Obesity; insulin resistance; pancreas intact
• Receptor does not bind to insulin as well as
it used to
• Hyperglycemia develops slowly
• Risk Factors: genetic predisposition;
overweight, over 45 y/o, sedentary lifestyle,
women who have had a baby over 9 lbs,
and low HDL levels

38. Gestational Diabetes
• Associated with type 2 diabetes
• Glucose intolerance with pregnancy
• increased risk of diabetes later on if it
continues >6 weeks after pregnancy

40. Acute Hyperglycemia
• Early Signs
 Blood sugar >180 mg/dL
 Blurred vision
 Ketones, dry skin, fatigue
 Thirsty, increased urination
• Late Signs
 Blood sugar > 240 mg/dL
 Nausea/vomiting
 Deep/rapid breathing
 Large ketones in urine, fruity breath
• Some patients don’t sense changes because of neuropathy

41. Acute Hypoglycemia
• Causes: over treatment with insulin, missed meal,
exercising when insulin is peaking, or stress
• Early Signs: tachycardia, hunger, headache, dizziness,
sweating, shaking, pale skin, and tingling around the
mouth
• Late Signs: slurred speech, confusion, sudden
moodiness, clumsiness, jerky movements, seizures,
and syncope
• Treatment: quick action is essential

42. Obesity: BMI Classification
• Underweight <18.5
• Normal Weight 18.5 to 24.9
• Overweight 25 to 29.9
• Obese >30

43. Obesity: Fat Locations
• Subcutaneous Fat
Necessary for thermal control
• Intra-abdominal Fat
Abdominal obesity is the most important
factor in determining pre-diabetic state
1 in 5 adults have metabolic syndrome
Goal: avoid fat around organs, especially the
liver

44. Obesity: Hormonal Regulation
• Fat
 Largest and most active endocrine organ
 Releases 50 hormones
• Adiponectin
 Signals to the brain that we are full
 As fat cells get bigger, less is released