ERU: Endocrine

Question 1

Hemocrine (endocrine cells)

Answer 1

Releases hormones, travel through bloodstream, attatch to cell receptor

Question 2

Autocrine (endocrine cells)

Answer 2

Releases hormnes and attatches to receptors on itself

Question 3

Paracrine (endocrine cells)

Answer 3

Hormones released and binds to cells nearby

Question 4

Pituitary gland (hormone released, structure and function)

Answer 4

Multiple, Glandular/ neuronal, Multiple

Question 5

Pineal (hormone released, structure and function)

Answer 5

Melatonin, neuronal

Question 6

Thyroid gland (hormone released, structure and function)

Answer 6

Thyroid, Follicular, Multiple

Question 7

Parathyroid gland (hormone released, structure and function)

Answer 7

PTH, Glandular (chief cells), calcium regulation

Question 8

Adrenal gland (hormone released, structure and function)

Answer 8

Cortisol, Aldosterone, etcl Glandular w/cortex + medullar, Multiple

Question 9

Pancreas (hormone released, structure and function)

Answer 9

Insulin + Glucagon, Glandular, Glucose regulation

Question 10

Zones of adrenal cortex (3)

Answer 10

Zona glomerulosa, zona fasciculata, zona reticularis (out to in)

Question 11

What produces aldosterone?

Answer 11

Zona glomerulosa (of adrenal cortex)

Question 12

What produces cortisol?

Answer 12

Zona fasciculata and zona reticularis (of adrenal cortex)

Question 13

What produces adrenaline?

Answer 13

Medulla of adrenal gland

Question 14

Cortisol (synthesis, mechanism of action and effects)

Answer 14

• From cholestrol + adrenal glands, hydrophobic and binds to cortisol binding protein.
• Intracellular receptors, altered protein synthesis and cell function.
• Fight or flight response (increased metabolism, immune supression, cardiovascular)

Question 15

Cushing’s disease

Answer 15

Over production of cortisol (from tumours, hyperglycaemia, increased appetite, lethargy)

Question 16

Addison’s disease

Answer 16

Under production of cortisol (Autoimmune destruction of adrenal gland, hypoglycaemia, lethargy, vomiting)

Question 17

Aldosterone (synthesis, mechanism of action and effects)

Answer 17

• Low BP sensed by kidneys, Angiotensin II secreted
• Arteriole constriction, Aldosterone release and ADH release -> water retention
• Regulates BP by NA and K levels

Question 18

Adrenaline/ norepinephreine (synthesis, mechanism of action and effects)

Answer 18

• Hypothalamus- splanchnic nerve, acetylcholine and stimulates adrenaline release. Stored in chromaffin cells. (Adrenal glands)
• Hydrophillic, altered protein function, cytoplasmic memory
• Fight/flight

Question 19

Glucagon (synthesis, mechanism of action and effects)

Answer 19

• pancreas a-cells
• Break down glycogen into glucose
• Raises blood sugar

Question 20

Insulin (synthesis, mechanism of action and effects)

Answer 20

• Pancreas B-cells
• Inhibits glucose production and allows glucose uptake into muscles and adipose tissues
• Lowers blood sugar

Question 21

Type 1 diabetes

Answer 21

Fail to secrete or produce insulin

Question 22

Type 2 diabetes

Answer 22

Fail to respond to insulin

Question 23

Which diabetes is more common in dogs and cats?

Answer 23

Dogs- Type 1, Cats- Type 2

Question 24

Anatomy of dog vs pig thyroid gland

Answer 24

Dog- 2 lobes on either side of trachea, Pig- Bridge across trachea

Question 25

What is the thyroid gland made of?

Answer 25

Follicles filled w/colloid. Surrounded by follicular epithelium and capillaries

Question 26

Thyroid hormone derivation

Answer 26

Amino acid tyrosine + iodine

Question 27

Tyroglobuline

Answer 27

Precursor to thyroid hormone.

Question 28

T4

Answer 28

4 iodine attatched. Most commonly released, longer half-life and converts to T3. Hydrophobic

Question 29

T3

Answer 29

3 iodine attatched, more active and higher receptor affinity. Hydrophobic

Question 30

Effects of thyroid hormone (3)

Answer 30

- Cardiovascular (increased responsiveness and higher sensitivity to adrenaline/noradrenaline) - Growth (some GH regulation, crucial to CNS development) - Metabolism (Increased thyroid hormone= increased basal metabolic rate)

Question 31

How does Ca move into cell?

Answer 31

High extracellular, low intracellular, through Ca2+ channels

Question 32

Role of Calcium in cells

Answer 32

Acts as signalling ion, able to activate intracellular processes

Question 33

Body parts involved in Ca homeostasis (3)

Answer 33

- Gut: Diet (increase) vs Faeces (loss) - Bone: daily bone turnover - Kidneys: urine (loss)

Question 34

Hormones that regulate Ca homeostasis

Answer 34

PTH, Calcitonin and Active vitamin D

Question 35

PTH (synthesis, mechanism of action and effects)

Answer 35

- Stored in chief cells and released when low Ca in circulation - Activated Ca2+ channels - Increases bone and kidney Ca release

Question 36

Active Vitamin D

Answer 36

From kidneys, synthesizzes proteins involved in Ca handling. Acts on Gut

Question 37

Calcitonin (synthesis, mechanism of action and effects)

Answer 37

- From C-cells (in Thyroid gland) when high blood Ca - Bone, inhibits bone reabsorption and Kidneys, reduces reabsorption

Question 38

Magnesium homeostasis mechanisms

Answer 38

- Through diet and kidneys - Not through bone or hormones

Question 39

PTH effect on bone (Ca regulation)

Answer 39

- Releases Ca2+ salts through osteoblasts (fast) - Breakdown hydroxyapatite crstals by osteoclasts (long term)