Adrenal Gland

Question 1

ACTH-dependent: higher than normla plasma ACTH
- pituitary hypersecretion of ACTH
- ectopic secretion of ACTH by non-pituitary tumor
ACTH-dependent: lower than normal plasma ACTH
- exogenous administration of steroid
- adrenocortical tumor

Answer 1

hypercortisolemia

Question 2

addison disease

Answer 2

autoimmune destruction of adrenal cortical cells
hypocortisolemia

Question 3

supramaximal conc of cortisol

Answer 3

• protein breakdown
• suppression of protein synthesis
• hyperglycemia and elevated fatty acids
• bone breakdown
• atrophy of adrenal cortex
• admin of exogenous cortisol

Question 4

physiological and permissive effects of cortisol

Answer 4

• net protein catabolism
• net glycogen synthesis
• increase EPI synthesis
• cortisol is permissive for actions of: NE, EPI, ADH, GH, glucagon

Question 5

rate limiting step of synthesis of cortisol

Answer 5

cholesterol -> prognenolone

Question 6

synthesis, secretion and MOA of cortisol

Answer 6

CRH stimulates ACTH release which acts on adrenal cortex to release cortisol
- physical stress, infection, hypoglycemia, psychological stress all act positively on CRH to stimulate ACTH and cortisol

Question 7

cortisol is released from

Answer 7

zone fasciculata of cortex

Question 8

metabolism of catecholamines
uptake by:

Answer 8

axon terminals: uptake 1 system
target tissues: uptake 2 system

Question 9

metabolism of catecholamines
enzymatic degradation by:

Answer 9

MAO in axon terminals
COMT in target cells

Question 10

physiological effects of catecholamines

Answer 10

Question 11

MOA of catecholamines:
alpha 2 ->

Answer 11

pancreas: inhibits insulin secretion
EPI and NE

Question 12

MOA of catecholamines:
beta 2 ->

Answer 12

bronchial smooth muscle: dilates bronchial airways
liver: stimulates glycogenolysis and gluconeogenesis
pancreas: increases glucagon secretion
fat: stimulates lipolysis
EPI selectivity

Question 13

stimulation of catecholamine secretion

Answer 13

• hypoglycemia, stress, physical exercise
  activates SNS and preganglionic autonomic nerves
  secretion of ACh, NE and EPI

Question 14

Synthesis and secretion of catecholamines

Answer 14

tyrosine converted to DOPA by tyrosine hydroxylase
DOPA converted to dopamine by AA decarboxylase
dopamine converted to NE by DBH
NE converted to EPI by PNMT
cortisol acts on PNMT

Question 15

EPI and NE are released from

Answer 15

the medulla