Haematopoiesis Flashcards
What are the three phases of the developmental pathway of erythropoiesis?
Phase 1 = ribosome synthesis
Phase 2 = Hgb accumulation
Phase 3 = ejection of nucleus
Immature form of RBC
Reticulocyte
Where is EPO used in erythropoiesis?
In the erythropoietin dependent path.
Iron dependent for what stage of erythropoiesis?
From erythroblasts to reticulocytes
How long can one RBC cell live?
100 - 120 days
What stage is this?
“synthesis of hemoglobin “
Proerythroblast
What stage is this?
“Nucleoli disappear”
Early normoblast
What stage is this?
“Hemoglobin starts appearing”
Intermediate normoblast
In the late normoblast, what happens?
The nucleus starts to disappear
What happens to the reticulum in reticulocyte and matured RBC?
Reticulum is formed in reticulocyte but it disappears when matured.
Role of vitamin C in erythropoiesis
Helps in iron absorption
_________ is needed for absorption of vitamin B12
Intrinsic factor
Androgen,_____, ______ and ACTH are hormones needed in erythropoiesis
Growth Hormone , Thyroxine
**RBC is slightly higher in male because androgen is for male sexual reproduction.
Three types of vitamin B that is needed in erythropoiesis
Vitamin B6, B12 and B9 (folic acid)
What is another name for erythropoetin?
Haemopoetin
Erythropoietin (EPO) is a glycoprotein cytokine produced in the _________
Kidney
Synthetic EPO is used clinically to treat ________
Anaemia
_______ stimulates EPO production, which then stimulates erythrocyte production in bone marrow
A state of reduced oxygen carrying capacity (hypoxia)
_______ are also used as illegal sports enhancing drugs
Synthetic EPO , so the athletes can increase number of RBC, which in turn increases aerobic capacity
How EPO increases production of RBC?
Hint: Three ways it affects
- promotes pronormoblast production
- Shorten transition time in normoblast stage
- promote early release of reticulocytes
Name the six other sites where EPO has an effect on:
- Brain (protection form ischemia)
- endothelium (vascular tone)
- heart (protection form ischemia)
- myoblast (wound healing)
- white fat
- bone (remodeling)
There is a decrease in cell size as RBC matures. True or False
True
Two changes in intermediate normoblast
Loss of mitotic activity and hemoglobinization
Change of RBC shape from _______ to _____ as it matures.
Globular , biconcave