8.4 Pituitary Hormones

Question 1

Endocrine System

Answer 1

• Controls and regulates metabolism (energy production, growth, food and electrolyte imbalance, stress balance)

Question 2

Endocrine Glands

Answer 2

• Secrete and regulate hormones (chemical substances that cells release to control other cells. They can target specific areas of the body or be diffuse in effect)

Question 3

Anterior/Posterior Pituitary Gland

Answer 3

Anterior
- GH (Growth Hormone)
- ACTH (Adrenocorticotropic Hormones)
- TSH (Thyroid Stimulating Hormone)
- MSH (Melanocyte Stimulating Hormone)
- PRL (Prolactin)
- Gonadotropic Hormone
- FSH (Follicle Stimulating Hormone)
- LH (Luteinizing Hormone)

Posterior
- OT (Oxytocin)
- ADH (Antidiuretic Hormone)

Question 4

How Hormones are Regulated

Answer 4

• Based on negative feedback loops
• Negative feedback loops prevent the endocrine system from becoming overactive due to mechanisms that inhibit products (Feedback inhibition)
• It recognizes when its hormones are getting too much to stop the body from producing the hormone

Question 5

Pan-Hypopituitarism

Answer 5

• A loss of all anterior pituitary hormones (leaving only posterior hormones intact)
• Most commonly caused by a tumor

Growth Hormone (helps body grow appropriately)
- Short stature
- Epiphyseal fusion
- Stunted bone growth
- Increased insulin sensitivity

Gonadotrophins
- Absence of sexual maturation or loss of secondary sexual characteristics
- Atrophy of genitalia, prostate glands, breasts
- Amenorrhea without menopausal symptoms
- Decreased spermatogenesis

ACTH (Adrenocorticotropic Hormone)
- Hypoglycemia
- Hypotension
- Hyponatremia
- Hyperkalemia
- Severe anorexia
- ADRENAL APOPLEXY (bleeding into organs or loss of blood flow into an organ)
- Circulatory Collapse

TSH (Everything slows down)
- Short stature
- Dry course skin, pallor, jaundice
- Constipation
- Bradycardia
- Dyspnea
- Delayed dentition

ADH (Antidiuretic Hormone)
- Polyuria
- Polydipsia
- Dehydration

Question 6

Pituitary Hyperfunction

Answer 6

• Excess release of pituitary hormones
• Most often caused by a tumor

Increased Growth Hormone (Gigantism)
- Increased in muscular growth and vertical height
- Acromegaly (develops after epiphyseal plates have closed which causes changes in facial features such as overgrowth of head, lips, tongue, facial hair, disproportionate face and jaw to the body)

• Difference between acromegaly and gigantism is whether it began when the epiphyseal plates have closed or not.

Question 7

SIADH

Answer 7

• Syndrome of inappropriate ADH
• ADH helps the body retain water
• Body produces too much ADH
• Retaining too much water
• Serum sodium becomes diluted (fluid volume excess)
• Serum sodium goes down but urine specific gravity goes up (because fluid cannot be expelled)

S/S
- Anorexia
- N/V
- Irritability
- Personality Changes
- Seizure (if sodium goes too low)

Treatment
- Fluid restriction
- Lasix to pull off extra fluid
- Accurate weight EVERYDAY

Question 8

Diabetes Insipidus

Answer 8

• Not producing enough ADH
• Causes you to lose significant amount of fluids
• Serum sodium increases because you are dehydrated

S/S
- Polyuria
- Polydipsia
- Irritability
- Increased thirst
- Increased serum sodium

Treatment
- Synthetic ADH (vasopressin or DDVAP)