REGULATION OF ERYTHROPOIESIS
Wednesday 4 October 2017
WHAT IS ERYTHROPOIESIS?
- IT IS ACTUALLY A PROCESS OF WHICH THE RED BLOOD CELLS (RBCs)OR ERYTHROCYTES IS FORMED IN THE BONE MARROW
REGULATION OF ERYTHROPOIESIS IS CRUCIAL IN OUR BODY. IT MUST NOT FALL AND NOT RISE FROM THE OPTIMUM RANGE!
WHY IT MUST NOT FALL?
- TO SUPPLY OXYGEN FROM LUNGS TO BODY TISSUES
WHY IT MUST NOT RISE?
- BLOOD VISCOSITY MAY INCREASE
- MAY IMPEDE BLOOD FLOW.
Thinking logically you might suspect that because the primary function of erythrocytes is to transport O2 in the blood, the primary stimulus for erythrocyte production is low O2 levels. You would be correct, but low O2 levels do not stimulate erythropoiesis by acting directly on the bone marrow.Instead, it stimulates the kidneys to secrete the hormone erythropoietin into the blood, and this hormone in a domino effect stimulates the bone marrow to produce erythrocytes.
Erythropoietin acts on derivatives of undifferentiated cells that have already been committed to becoming red blood cells (RBC’s), stimulating the proliferation and maturation of these cells into mature RBCs.This increase in erythropoietic activity elevates the number of circulating RBCs, thereby raising the O2 carrying capacity of the blood and restoring the delivery of O2 to the body tissues to normal. Once the O2 level in the tissues of the kidneys is brought back to normal, erythropoietin secretion is turned down until it is needed again. This is an example of a negative feedback mechanism.
1. TISSUE OXYGENATION
; OUR BODY TISSUES NEED A SUFFICIENT AMOUNT OF OXYGEN SUPPLIES.
CONDITION SUCH AS :-
- ANEMIA
- HIGH ALTITUDES
- CARDIAC FAILURE
- RESPIRATORY PROBLEMS
MAY LEAD TO INSUFFICIENT AMOUNT OF OXYGEN REACHING THE BODY TISSUES!
ALL THE CONDITIONS ABOVE HAVE ONE COMMON PROBLEM WHICH IS LEAD TO TISSUE HYPOXIA.
*The term hypoxia is a condition where the tissues are not oxygenated adequately, usually due to an insufficient concentration of oxygen in the blood. The oxygen deprivation can have severe adverse effects on various body cells that need to perform important biological processes.
ERYTHROPOIETIN(EPO)?
- A hormone secreted by the kidneys that increases the rate of production of red blood cells in response to falling levels of oxygen in the tissues.
SITES OF PRODUCTION :-
- KIDNEYS
- LIVER
- BRAIN
- UTERUS
ROLE OF EPO IN ERYHTROPOIESIS ;
- STIMULATES PROERYHTROBLAST FORMATION
- CAUSES CELLS TO PASS THROUGH VARIOUS STAGES OF ERYHTROPOIESIS RAPIDLY
2. VITAMINS
; IF NOT SUFFICIENT, RBCs WILL HAVE NUCLEUS WHICH IS ABNORMAL
- Vit B12 & Folic Acid
- ESSENTIAL FOR FORMATION OF THYMIDINE TRIPHOSPHATE
- ESSENTIAL BUILDING BLOCK OF DNA
- Vitamin C (immune system)
- POTENTIATE THE EFFECT OF FOLIC ACID
- IRON ABSORPTION
- Pyridoxine
- COENZYME FOR CONDENSATION OF GLYCINE AND SUCCINYL-CoA
- INVOLVE IN HAEMOGLOBIN PRODUCTION
- Riboflavin & Pantothenic Acid
- HEME FORMATION
- CELL GROWTH AND FORMATION
3. MINERALS
- IRON
- COPPER
- Ceroplasmin
- Necessary for Iron transfer from storage sites.
- COBALT
- NICKEL & MANGANESE
4. PROTEINS
; Adequate protein diet ESSENTIAL and plays role in Globin formation.
5. HORMONES
- TESTOSTERONES
- GROWTH HORMONES
- THYROID HORMONES
- CORTISOL
- ACTH
6. OTHER CONDITIONS : -
- EXERCISES (STIMULATE RBCs PRODUCTION)
- EXCITEMENT
- MENSTRUATION (CIRCULATE NEW BLOOD)
- PREGNANCY (DEMAND OF FOETUS)
- MENOPAUSE (DUE TO HORMONES)
THANKS FOR READING :)
1 comments
bmedicalscience2020 said...Such a great knowledge to learn.