Adrenal Gland + pancreas

Question 1

What are teh parts of the adrenal gland from the inside out?

Answer 1

• Medulla
• Zona reticularis (produces mineralocorticoids)
• Zona fasiculata (produces glucocorticoids)
• Zona glomerulosa (produces adrenal androgens)

Question 2

What is the most prominent steroids released from the adrenal cortex?

Answer 2

1. Zona reticularis - mineralocorticoids - aldosterone (from corticosterone)
2. Zona fasiculata - Glucocorticoid - Cortisol (from corticosterone)
3. Zona glomerulosa - Androgens and Estrogens

Question 3

What is released by the adrenal medulla?

Answer 3

1. Epinephrine (80%)
2. Norepinephrine (20%)

Question 4

What are the parent molecules of adrenal hormones?

Answer 4

1. Pregnane: produces pregnenalone
2. Androstane: produces testosterone
3. Estrane: produces estradiol

Question 5

How are androgens synthesized?

Answer 5

DHEA creates androstenedione which creates testosterone which creates DHT

Question 6

How are estrogens synthesized?

Answer 6

Estrone = androstenedione + aromatase

Estradiol = estrone OR testosterone + aromatase

Estriol = Estradiol

Question 7

What is aldosterone’s function?

Answer 7

Regulates body fluid volume by promoting Na+ retention and K+ excretion in the distal and collecting tubules of nephron in kidney

Question 8

What controls aldosterone?

Answer 8

1. Renin angiotensin system
2. Circulating K+ concentrations

Question 9

What is hyperaldosteronism?

Answer 9

Primary (Conn’s syndrome) or secondary; results in hypernatremia, hypokalemia and hypertension

Question 10

What is adrenogenital syndrome?

Answer 10

Adult biological females: masculinisation, facial hair, deepening of voice

Newborn biological females: pseudohermaphrodism

Adult biological males: no effect

Pubertal biological males: pseudopuberty

Question 11

What is adrenarche

Answer 11

part of puberty that involves gradual maturation of the adrenal glands and the production of more androgens

Question 12

What is the cortisol stress pathway?

Answer 12

1. Stress/diurnal rhythm triggers hypothalamus to produce CRH
2. CRH stimulates anterior pituitary to release ACTH
3. ACTH triggers adrenal cortex to release cortisol

Question 13

What does cortisol do?

Answer 13

1. increase blood glucose by stimulating gluconeogenesis and glucose uptake by muscle
2. Increase blood AA by stimulating protein degradation
3. Increase blood fatty acids by stimulating lipolysis

Question 14

What are glucocorticoids’ actions outside energy generation?

Answer 14

1. vascular collapse during stressful events
2. atrophy of lymphatic system
3. anti inflammatory effects

Question 15

What is cushings syndrome?

Answer 15

Hypersecretion of CRH or ACTH, symptoms include excess glucose, fat depostiion and facial hair excess

Question 16

What is addisons disease?

Answer 16

hyposecretion of cortisol, symptoms include weakness, weight loss, hypotension and hypoglycemia

Question 17

What is the primary alarm response?

Answer 17

1. surge of catecholamine (eye dilation, heart rate)
2. increase in basal metabolic rate
3. increase blood flow
4. hypatic glycogenolysis

Question 18

What is the secondary resistance response?

Answer 18

1. continued mobilisation of glucose for central organs
2. breakdown of alternative energy stores (lipids, proteins)
3. continued primary alarm response

Question 19

What is the tertiary exhaustion response?

Answer 19

1. muscle wasting, hyperglycemia
2. atrophy of immune system and gastric ulcers
3. vascular derangements

Question 20

What is the function of the adrenal medulla?

Answer 20

Release norepinephrine and epinephrine and act as extension of sympathetic nervous system.

Question 21

What is the difference of epinephrine inding to alpha receptor and beta receptor?

Answer 21

alpha: constricts blood vessel
beta: dilates blood vessel

Question 22

What are hormones released by the pancreas?

Answer 22

1. insulin and amylin (from B or beta cells)
2. glucagon (from alpha cells)
3. somatostatin (released from D or delta cells)
4. pancreatic polypeptide, released from PP or F cells

Question 23

What does amylin do?

Answer 23

Released with insulin and slows down appearance of glucose in the blood

Question 24

WHat does somatostatin do?

Answer 24

Released in response to increased glucose and amino acid levels; inhibits digestive absorptive processes

Question 25

What does the pancreatic polypeptide do?

Answer 25

inhibits the secretion of pancreatic enzymes including somatostatin

Question 26

What is the pathway of insulin secretion?

Answer 26

1. Glucose taken up by GLUT 2. Glucose undergoes glycolysis to make ATP/ADP 3. ATP fuels Katp channel which allows release of K+ 4. Release of K+ hyperpolarizes the cell which cuases Calcium channel to open 5. Intake of calcium triggers insulin secretion

Question 27

What's the difference between Type I and type II diabetes?

Answer 27

I: lack of insulin secretion II: lack of insulin sensitivity

Question 28

How does insulin facilitate glucose transport?

Answer 28

1. Insulin creates a signal cascade in a hepatocyte that triggers the conversion of intracellular glucose to glucose-6-phosphate, which lowers intracellular concentration shifting the gradient to move inwards through GLUT2 2. Insulin creates a signal cascade that triggers the exoctyosis of GLUT4 transporters into the membrane to increase glucose permeability

Question 29

What are two ways blood glucose is increased and ways blood glucose is decreased?

Answer 29

Increased: glucose absorption from digestive tract + hepatic glucose production (glycogenolysis, gluconeogenesis) Decrease: transport of glucose into muscle (storage), energy production, urinary excretion of glucose

Question 30

How is insulin first synthesized?

Answer 30

Proinsulin cleaves connecting peptide (C-peptide) to form A chain and B chain connected by disulfide bonds.

Question 31

How does insulin affect carbohydrate concentrations?

Answer 31

1. Facilitiates glucose transport into the cell by keeping intracellular concentrations low and exocytosing GLUT vesicles 2. Inhibits glycogenolysis in liver 3. Inhibits gluconeogenesis by reducing circulating amino acids

Question 32

What are insulin's actions on fat?

Answer 32

1. Inhibits lipolysis 2. Stimulates fatty acid uptake in adipose tissue 3. Stimulates glucose uptake and conversion to triglycerides

Question 33

What are insulins actions on protein?

Answer 33

1. Promotes amino acid uptake 2. stimulate protein synthesis 3. inhibits protein degradation

Question 34

What is the pathway of insulin deficiency in the liver?

Answer 34

1. Increase in glycogenolysis 2. Hyperglycemia 3. Glucosuria (glucose in urine) 4. Pull of water into nephron 5. constant urination 6. dehydration 7. low blood volume, increase in drinking, cell shrinkage 8. Low blood volume + nervous system malfunction

Question 35

What is the pathway of insulin deficiency in the cell?

Answer 35

1. Decreased glucose uptake in cells 2. intracellular glucose deficiency + hyperglycemia 3. Polyphagia (constant hunger)

Question 36

What is the insulin deficiency pathway in terms of fats?

Answer 36

1. Increased lipolysis, low triglyceride synthesis 2. increased blood fatty acids 3. utilization oof ketone bodies as energy 4. ketosis 5. metabolic acidosis 6. increased ventilation to maintain blood pH, diabetic coma

Question 37

What is the pathway of insulin deficiency in terms of protein?

Answer 37

1. decrease in amino acid uptake + increase in protein degradation 2. increase in blood amino acids + muscle wasting 3. increase in gluconeogenesis from amino acids 4. aggravation of hyperglycemia

Question 38

What is glucagon's effect on carbohydrates?

Answer 38

Stimulates hepatic glycogenolysis (via phosphorylase) and gluconeogenesis (via glycogen synthase)

Question 39

What is glucagon's effect on fats?

Answer 39

1. promotes fat breakdown and release of tri/di/monoglyceride lipase's from fats 2. inhibits hepatic ketogenesis (conversion of free fatty acids to ketone bodies)

Question 40

What is glucagon's relationship to proteins?

Answer 40

Promotes hepatic protein catabolism to free amino acids for gluconeogenesis.

Question 41

How do alpha and beta cells respond to a high concentration of amino acids in the blood?

Answer 41

Beta: increase in production of insulin to take up amino acid into cells Alpha: increase in production of glucagon to release glucose to fuel insulin-induced protein synthesis