click below
click below
Normal Size Small Size show me how
Block 6-aa products
Block 6 amino products, Heme and Bilirubin
Question | Answer |
---|---|
Three specialized products derived from tyrosine? | Thyroid hormones: T3, T4 |
Two specialized products derived from Tryptophan? | Serotonin, Niacin (NAD, NADP) |
Two specialized products derived from Arginine? | Creatine (arginine + glycine) & Nitric Oxide |
Two specialized products derived from Glutamate? | Glutamate as a neurotransmitter & GABA |
One specialized product of Histidine? | Histamine |
What three amino acids are essential in the synthesis of purines or pyrimdines? | glycine, glutamine, aspartate |
One specialized product that uses the entire structure of glycine? | Heme |
Where does Heme synthesis occur? | liver |
What are some heme-containing proteins? | hemoglobin, myoglobin, cytochromes (P450, ETC) |
What are some heme-containing enzymes? | peroxidases, catalases |
What 2 enzymes does lead poisoning inhibit? | ALA dehydratase & Ferrochelatase |
What enzyme combines succinyl-CoA and glycine to start the Heme pathway? | ALA (aminolevulinic acid) synthetase |
What is porphyria? | rare enzyme deficiency in the heme pathway |
Why does skin begin chronic inflammation and blistering with porphyria? | UV-light converts accumulated intermeadiates from the Heme pathway |
What is the difference in the concentration of ALA in Vitamin B6 deficiency and lead poisoning? | Ala decreased in B6, increased in Lead poisoning |
From where does bilirubin originate? | older RBCs lysed in spleen, heme released and converted to bilirubin by spleenic macrophages |
How does bilirubin travel from the liver to the gall bladder? | It is insoluble so it rides albumin |
What is a way the hepatocytes make bilirubin more soluble? | conjugate with glucuronic acid, in a UDP-glucuronate...conjugated bilirubin or bilirubin glucuronate |
What does bilirubin contribute to the gall bladder, it's storage site? | green color is due to bilirubin glucuronate |
What makes poop brown? | bilirubin glucuronate conveted to urobilinogen which becomes sterocobilin (stands for brown sheete) |
How could a big pile of feces indicate you had a bile duct blockage? | it would be clay colored |
What makes urine yellow? | Lemonade...or a portion of urobilinogen converted to urobilin and excreted in urine |
Summarize what makes the following colors? Brown Feces, Green Bile, Yellow urine | urobilinogen to stercobilin in feces billirubin glucuronate in gall bladder urobilinogen to urobilin in urine |
You can indirectly measure bilirubin by checking the level of: | unconjugated bilirubin |
What conditions increase indirect/insoluble bilirubin? | Hemolysis from sickle cell, thalassmia, or G6PDH; Crigler - Najar; Gilberts syndrome; Low levels of UDP-Glucuronate in newborn |
What conditions increase direct/soluble bilirubin? | Hepatic damage that results in failure to secrete conjugated bilirubin into bile duct and/or bile duct obstruction |
What causes Jaundice? | increase in indirect or direct bilirubin, or both. |
What is the problem with accumulation of indirect, lipid soluble billirubin? | crosses blood brain barrier to cause death |
Why does conjugated bilirubin not act in this manner? | It is secreted in the urine |
What is total bilirubin? | unconjugated + conjugated bilirubin |
What are three examples of hemolytic crisis? | episodes of hemolysis in G6PDH deficiency Sickle Cell crisis Thalassemia |
What happens in Crigler-Najar syndrome | genetic defect in UDP-glucuronyl Transferase |
What is a symptom of the less severe Gilbert syndrome | inferior sclera is faint yellow |
If you damage your liver through alcoholism, what enzymes are increased in the blood? | AST is greater than ALT |
What increases in viral Hepatitis in the blood? | ALT is greater than AST |