Shared Flashcard Set

Details

Chemistry- Porphyrins, Iron and Lead
test 4
32
Health Care
Undergraduate 4
10/27/2009

Additional Health Care Flashcards

 


 

Cards

Term
What are the 3 major porphyrins?
Definition
uroporphyrin, coproporphyrin, protoporphyrin
Term
Where does heme synthesis occur?
Definition
in all cells; greatest in bone marrow and liver
Term
What is the rate limiting step in heme synthesis?
Definition
ALA synthetase
Term
How is ALA synthetase regulated?
Definition
by heme- excess heme inhibits; deficit of heme stimulates
Term
A group of disorders that demonstrate a defect in the heme biosynthetic pathway, resulting in abnormal porphyrin metabolism and overproduction of heme precursors.
Definition
porphyrias
Term
What are the 2 ways to classify porphyrias?
Definition
erythropoietic or hepatic; neurological or cutaneous
Term
Which type of porphyria is characterized by acute attacks of abdominal pain, constipation, neuromuscular signs, and psychotic behavior?
Definition
neurological porphyrias
Term
Which type of porphyria is characterized by photosensitivity and skin lesions without neurological signs or symptoms?
Definition
cutaneous
Term
What are the 3 neurological porphyrias?
Definition
acute intermittent porphyria; variegate porphyria; coproporphyria
Term
What are the 3 cutaneous porphyrias?
Definition
congenital erythropoietic porphyria; protoporphyria; porphyria cutanea tarda
Term
What is the most common neurological porphyria?
Definition
acute intermittent porphyria
Term
What 2 compounds are seen in urine during acute attacks of neurological porphyrias?
Definition
ALA and PBG
Term
Which neurological porphyria is distinguished from the others by increased excretion of protoporphyrin and coproporphyrin in feces?
Definition
variegate porphyria
Term
What compounds are increased in cutaneous porphyrias?
Definition
URO, COPRO, PROTO
Term
What is the rarest and most severe cutaneous porphyria?
Definition
congenital erythropoietic porphyria
Term
Which porphyria is associated with erythrodontia?
Definition
congenital erythropoietic porphyria
Term
Which cutaneous porphyria is associated with increased PROTO and FEP in blood?
Definition
protoporphyria
Term
Which cutaneous porphyria usually is dormant until liver disfunction develops?
Definition
porphyria cutanea tarda
Term
Watson-Schwartz is the name of a colorimetric method used to measure what?
Definition
porphobilinogen (PBG)
Term
Which is more specific for porphyria- ALA or PBG?
Definition
PBG
Term
In lead poisoning, what happens to ALA? PBG? FEP?
Definition
increased ALA, normal PBG, increased FEP
Term
What sample should be used for blood lead and why?
Definition
whole blood because over 90% of lead is in erythrocytes
Term
Isolated elevated COPRO without other porphyrins elevated is associated with what disorder?
Definition
coproporphyria
Term
In iron deficiency, what happens to FEP?
Definition
increased- zinc replaces iron to form zinc protoporphyrin (FEP)
Term
What state does iron have to be in in order to be absorbed?
Definition
Fe 2+
Term
What is the transport protein for iron?
Definition
transferrin
Term
What is the major storage form of iron?
Definition
ferritin
Term
Where is most of the ferritin stored?
Definition
liver and bone marrow
Term
What kind of test is used to measure serum iron?
Definition
colorimetric
Term
What kind of test is used to measure ferritin?
Definition
immunoassay
Term
What is the single most reliable indicator of iron deficiency?
Definition
decreased ferritin
Term
What is the effect of iron deficiency on TIBC?
Definition
increased TIBC
Supporting users have an ad free experience!