Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Endocrine 2 > Pheochromocytoma and Paragangliomas > Flashcards

Pheochromocytoma and Paragangliomas Flashcards

1
Q

What is the rate limiting step of catecholamine synthesis?

A

Tyrosine -> dopa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the pathway from tyrosin to epinephrine? What cofactor are involved?

A

tyrosin - dopa - dopamine - NE -(PMNT)- epi

Cortisol is the cofactor for PMNT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What two ways are catecholamines removed from circulation?

A
  1. Reuptake by sympathetic nerve terminals

2. Metabolism through COMT or MAO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two metabolism pathways for epinephrine?

A

EPI -COMT-> metanephrinc -MAO-> vanillylmandelic acid

EPI -MAO->dihyroxymandelic acid -COMT->
vanillylmandelic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the two metabolism pathways for norepinephrine?

A

NE –COMT-> normetanephrine –MAO> vanillylmandelic acid

NE –MAO-> dihydroxymandelic acid –via COMT-> vanillylmandelic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the metabolic pathway for dopamine?

A

Dopamine -> (via COMT and MAO)-> homovanillic acid

sulfate conjugation -> renal excretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 types of Adrenergic receptors? and their

A

alpha1,2, beta1,2,3, Dopamine receptor1,2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What do a1 receptors mediate?

A

postsynaptic:

vascular/smooth muscle contraction = increases blood pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do a2 receptors mediate?

A

presynaptic: inhibit norep release

decrease BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do B1 receptors mediate?

A 
cause positive inotropic + chronotropic fx
increase:
renin release
lipolysis
bronchodilation
vasodilationglycogenolysis
increase norepi release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What do B2 receptors mediate?

A

bronchodilation and vasodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What do B3 receptors mediate?

A

regulates energy expenditure and lipolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do DA1 receptors mediate?

A

causes vasodilation in vascular beds @:

  1. cerebral
  2. renal
  3. mesenteric
  4. coronary vasculature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the selectivity of EPI and NE on adrenergic receptors?

A

EPI: slightly more active at A1
EPI+NE: equally active at alpha 2 and beta 1
EPI: MORE ACTIVE AT B2 receptor (this is why you give epi to asthma patients)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are paraganglia cells?

A

small organs consisting of mainly neuroendocrine cells

from embryonic neural crest

SECRETE CATECHOLAMINES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are Paragangliomas?

A

located in sympathetic paravertebral ganglia of thorax, abdoman, pelvis

usually secrete catecholamines and metanephrines

17
Q

What is the rule of 10s of pheochromocytomas?

A 
10%:
malignant
bilateral
extra-adrenal
calcified
in children
18
Q

What is the age range of highest incidence of pheos?

A

30-50s

19
Q

Where are paragangliomas usually found?

A

para-aortic sympathetic chain
origin of the inferior mesenteric artery
wall of urinary bladder
sympathetic chain in the neck or mediastinum

20
Q

What two syndromes are related to bilateral pheos?

A

MEN

Von Hippel-Lindau

21
Q

What syndrome is related to GISTs and paragangliomas (sympathetic or parasympathetic)

A

Carney-Stratakis dyad

22
Q

What syndrome is related to paragangliomas that are located in the skull base and neck, thorax, abdomen, pelvis

A

Familial paraganglioma (5 PGL syndromes)

23
Q

What is the difference between MEN 2A and MEN 2B? What traits do they both share?

A

BOTH: medullary thyroid cancer, pheo/paraganglioma

MEN2A: primary parathyroid hyperplasia
MEN2B: NO hyperPTH

24
Q

What is the genetic cause of MEN?

A

Chromosome 10q - RET mutation

25
Q

What happens a/w with RET:

  1. gain of fxn mutation:
  2. loss of fxn mutation:
A
  1. MEN 2A, 2B

2. Hirschsprung

26
Q

What is the CLASSIC TRIAD of Sx in a patient with a Pheochromocytoma?

A
  1. Episodic headache
  2. Sweating
  3. Tachycardia

*varied BP readings

27
Q

What are typical symptom “spells” of pheo?

A 
forceful heartbeat
pallor(FLUSHING IS NOT TYPICAL in pheo)
tremor
headache
diaphoresis

-most pts with spells dont have pheo - some with essential HTN

Endocrine 2 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions