Trace Elements Flashcards
Which is the most abundant trace element?
Iron
What are the two types of dietary iron?
-Heme sources (Fe2+)
-Non heme sources (Fe3+)
Where is iron absorbed? To what efficacy?
proximal small intestine. 3-5%
What is the role of EPO in iron absorption?
It will stimulate iron absorption
What blood protein binds to Fe3+? Where does this binding occur?
transferrin in the blood
Why is it important that iron is bound?
Because it is otherwise and oxidative agent
Where is the most iron located in the body?
RBCs
What is the tissue binding protein of iron?
ferritin
Which two hydroxylases are associated with iron
Tyrosine and tryptophan
What two synthesis pathways is iron involved in?
Catecholamine and Serotonin
What is the main sign of iron deficiency?
anemia
What is the most common cause of iron deficiency?
blood loss
What is the most common way an animal lose blood and cause iron deficiency?
GI bleeding (tumors, parasites, etc)
List two reasons young animals may need iron supplementation?
-low iron stores
-rapid growth demands expansion of blood volume
What is secondary iron deficiency?
There are normal iron levels, but heme cannot be synthesized
What are two causes of iron deficiency?
-Chronic lead poisoning
-Vit B6 deficiency (pyridoxal phosphate is a cofactor for delta-ALA synthase)
Iron toxicity is rare in vet med, true or false?
true
Why is zinc important?
It is an important component of many proteins including >100 enzymes involved in metabolic pathways
Where is zinc absorbed and to what efficacy?
the proximal small intestine at 20-30%
Why is zinc not stored?
because it has such a high turnover rate
How is zinc transported in the blood?
Albumin
What are 6 zinc containing enzymes?
-Pepsidases/collagenases
-carbonic anhydrase
-superoxide dismutase
-pyruvate carboxylase
-retinal reductase
-alkaline phosphate
What 4 receptors utilize zinc finger motifs?
-RAR
-RxR
-VDR
-Steroid receptors
What amino acid does zinc coordinate with for zinc finger formation?
cysteine
