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Flashcards in Heme Deck (37):
1

how does heme synthesis start

ALA synthase is activated, synthesizes ALA from succinyl - CoA and glycine.

2

where is ALA synthase located

mitochondria

3

what happens to ALA after its made

gots to cytosol, where it turns into PBG from PBG synthase

4

what happens to PBG after it's made

jointed to form uroporphyrinogen by uroporphyirogen synthase III

5

what is the committed step of heme synthesis

ALA synthase

6

what inhibits heme synthesis

heme

7

how does synthesis of p450 enzymes affect heme

consumes it and increases synthesis

8

in general what do problems in synthesis of heme lead to

incrase in ALA synthase activity

9

porphyrias

diseases of heme synthesis

10

what causes AIP

deficiency of porphobiliinogen deaminase

11

symptoms of AIP

urine gets a dark red color
confusion
sharp abodminal pain

12

what is PCT caused by

deficiency of uroporphyrinogen decarbosylase

13

symptoms of PCT

urine that emits pink gluorence under UV
photosensitivity of skin

14

what does lead inhibit

porphobilnogen synthase and ferrochelatase

15

symptoms of lead poisiong

simliar to porphyrias, prescne of lead adn heme precuros in urin

16

what is the half-life of RBCs

120 days

17

is bilirubin hydrophilic or hydrophobic

hydrophobic

18

where is bilirubin produced

spleen

19

how does bilirubin get to liber

binds to albumin

20

how is conjugated bilirubin secreted?

hepatocytes into bilirary capillaried and through gall duct

21

what is the compound that makes poo brown

urobilin

22

how do you get urobilin

spontaneous oxidation of urobilinogen

23

where does yellow color of urine come from

urobilins that were reabsorbed from gut

24

under normal conditions should you see bilirubin in the urine

no

25

is urobilin water solube?

yes

26

hyperbilirubinemia

serum bilirumb >1.5 mg/dL

27

kernitcterus

unconjuaged bilirubin crosses BBB and damages brain

28

what causes prehepatic jaundice

destruction of RBCs causes excess serum bilirubin that the liver can't deal with.

29

in prehepatic jaundice what type of bilirubin is in the serum

unconjugated

30

example of prehepatic jaundice

neonatal physiological juandice
hemolytic disease

31

symptoms of hepatocellular jaundice

pale feces and urine

32

in hepatocellular jaundice waht type of bilirubin is in serum

unconjugated

33

what casues hepatocellular jaundice

hepatitis, or acetaminophen poising

34

symptoms of cholestatic jaundice (obstruction)

pale feces
intense urine

35

what type of bilirubin in tissues and urine in choelstatic jaundice

conjugated

36

when do you see markers of ALT and AST

hepatocellular jaundice

37

what is in the urine in hemolytic jaundice

no bilirunbin