physiology

1. GURUNANAK INSTITUTE OF
PHARMACEUTICAL SCIENCE
& TECHNOLOGY
•

2. 1. INTRODUCTION-DEFINITION & SITE
OF ERYTHROPOIESIS
2. STAGES OF ERYTHROPOIESIS
3. DESCRIPTION OF THE STAGES
4. DURATION
5. FACTORS EFFECTING
ERYTHROPOIESIS
6. CONCLUSION
7. REFERENCE

3. DEFINITION:
process by which the origin,development
and maturatrion of RBCs occur.
SITE:
In intra uterian stage of RBCs are
produced from mesodermal yolk sack, liver
and spleen.
After birth produced from Red bone
marrow(RBM), skull,ribs and vertibrae.

4. Red bone marrow (RBM)
Pleuripiotent haemopoitic stem cell (PHSC)
Colony forming unit of erythroblast (CFU-E)
Proerythroblast
Erythroblast
Basophilic erythroblast
Polychromic erythroblast
Reticulocytes (Diapedesis)
Matured RBCs

5.  PROERYTHROBLAST:
Large cell , slightly alkaline in nature ,no
haemoglobin.
 BASOPHILIC:
Alkaline in nature , cell size smaller with no nucleus.
 POLYCHROMIC:
Cell size smaller with small nucleus, haemoglobin
starts to appear.
 ORTHOCHROMIC:
Cell size more smaller with small nucleus ,more
haemoglobin.

6. (contd...)
RETICULOCYTES:
Small cell,more stable haemoglobin,no
nucleus.
 MATURED RBCs:
Non-nucleated,alkaline,bi-concave in
shape.

7. It takes total 7-9 days for formation of Mature Red
Blood Cell. The duration is as follows-
A. Red Bone Marrow → Proerythroblast- 3 Days
B. Proerythroblast → Orthochromic ery- 2 Days
C. Orthrochromic ery → Mature RBC- 2 Days

8. Tissue hypoxia → Kidney (JG cells) → REF →
Erythropoietinogen → Erythropoietin →
RBM → ↑ RBC production.
↑ BMR → Tissue hypoxia → Kidney (JG cells) → REF
→ Erythropoietinogen → Erythropoietin →
RBM → ↑ RBC production.

9. OTHER FACTORS:
Interleukin I T- lymphocytes ↑ RBC
Androgen : ↑ Erythropoietin secretion → ↑
RBC production
Oestrogen : ↓ Erythropoietin secretion → ↓
RBC production
Vitamin B12, Intrinsic
factor & Folic acid.

10. Life span of erythrocytes is 120 days!
By the process , ERYTHROPOIESIS,
development and maturation of new
erythrocytes occurs . Thus the normal value
of erythrocytes remain constant in human
body.

11. 1.Haematology,Principles Of Physiology ,
Debasis Pramanik,4th Edition , Academic
Publishers, page no.- 74-78
2.The blood , Ross And Wilson Anatomy &
Physiology in Health and Illness,Anne
Waugh;Allison Grant,12th
Edition,Elsevier,page no.-66-67