(27) Thyroid

Question 1

(Actions of GH: Diabetogenic effect)

1. metabolism of what? anti or pro metabolism activity?
2. Causes what (pertaining to insulin)?
3. Increase or decrease lipolysis in adipose tissue?
4. blood insulin levels?

Answer 1

1. carbohydrates; anti-insulin activity
2. insulin resistance (decreass glucose uptake and utilization by muscle and adipose tissue)
3. increases
4. increases

Question 2

(GH: Effects on linear growth)

1. major role in stimulating body growht is via secretion of what?
2. IGF-1 stimulates proliferation of what cells? growth of what? proliferation of what?
3. IGF-1 also involved in growth of muscle by differentiation and proliferation of what? Stimulates uptake of what and synthesis of what? What is the result of all this?

Answer 2

1. IGF-1
2. cartilage cells; bones; chondrocytes
3. myoblasts; aa uptake and protein synthesis; increase lean muscle mass and organ size

Question 3

(More comments on GH)

1. Weight gain or loss? depends on what two things?
2. Does GH vary according to breed, sex, and season?

Answer 3

1. depends on whether IGF-1 (anabolic) or insulin resistance and hyperglycemia predominate (catabolic)

(most lose weight at first and then slowly gain as IGF-1 effects predominate)

2. yes

Question 4

(USes of GH)

1. approved and marketed for enhancing milk production in cows?
2. also application of GH to pigs - increase muscle decrease fat

Answer 4

1. yes

(administration of bovine somatotropin to lactating cows results in increased milk yeikd, this is controvesial

Question 5

(Pathophysiology of GH)

1. Classic human features are enlarged hands, feet and facial features - called what?

(Chronic excessive GH sec by AP cells)

1. weight loss or gain?
2. extremity enlargement or opposite?
3. growth of what two things
4. is age of onset of tumor important?

Answer 5

1. acromegaly
2. gain
3. enlargement
4. paws, chin skull
5. yes (role of pubertal hormones on epiphyseal plates and linear growth)

Question 6

just read this

PU/PD/PP (polyruria, polydipsia, polyplasia)

Answer 6

and this

Question 7

read this

lots of progesterone inhibis ovulation through negative feedback

Answer 7

Question 8

and this

Question 9

Treatment

(Canine Acromegaly)

1-3. What are three treatments?

(Feline Acromegaly: GH secreting tumor)

4-6. What are three ways to treat this?

Answer 9

1. stop progestin treatment
2. Ovx
3. block progesterone receptor (aglipristone)
4. irradiation of pituitary tumor
5. medical therapy using somatostatin analogs
6. hypophysecotomy

Question 10

(GH Deficiency)

(Dwarfism)

1. affected pups display what three things?
2. is puppy hair coat retained?
3. How about the skin? three things…

Answer 10

1. stunted growth, shrill bark, mental retardation (at 2 to 3 months)
2. yes
3. fragile skin, hyperpigmented, truncal alopecia

Question 11

(Pituitary Dwarfism)

1. Life span?
2. teeth?
3. hair loss?
4. secondary hypos of what are common?
5. external genitalia?
6. females ovarian cortex is what? etrus is what?

Answer 11

1. shortened
2. permanent dentition delayed or absent
3. bilateral symmetical alopecia
4. hypothyroidism and hypadrenocorticism
5. remain infantile
6. hypoplastic; irregular or shortened

Question 12

(Pituitary Dwarfism)

(Diagnosis)

1-3. What can be done (three things)

Answer 12

1. GH and IGF1 assay
2. GH stim tests (Ghrelin, GHRH, clonidine, xylazine)
3. Thyroid panel including TSH

Question 13

(Pituitary Dwarfism)

Treament

1-3. What are three treatments?

Answer 13

1. progestins (stimulate GH and IGF-1) * GH antiboides may develop if human or bovine Gh used
2. porcine GH can be used in dogs
3. thyroid supplementation