Long-term control of blood pressure

1. LONG TERM CONTROL OF
BLOOD PRESSURE
BY:
DR. MEHWISH QAMAR
ASSISTANT PROF. PHYSIOLOGY

2. Learning outcomes
• By the end of this lecture, the students should be able to:
• Define blood pressure
• Identify the control mechanisms of the blood pressure
• Explain the pathophysiology behind the renin angiotensin aldosterone
system
• Illustrate the mechanism involved in aldosterone effects on the
kidney

3. WHAT IS BLOOD PRESSURE?
The pressure exerted by the blood on the lateral walls of the blood
vessels.
Two components
1. Systolic blood pressure(SBP)--------120 mm of Hg
2. Diastolic blood pressure(DBP)-------80 mm of Hg
Pulse pressure (PP) = SBP-DBP = 120-80 = 40mm of Hg
Mean Arterial Pressure= DBP+ 1/3 PP=80+40/3= 93.3 mm Hg

4. Control of Blood Pressure
Occurs with in seconds to minutes
Rapid Control
Long Term Control
Rapid Control of Arterial Pressure
Occurs with in days and weeks
Long Term Control of Arterial Pressure

5. LONG TERM REGULATION OF
ARTERIAL PRESSURE

6. Renin-
Angiotensin-
Aldosterone
System

7. LIVER
KIDNEY ADRENAL CORTEX
KIDNEY
LUNGS
Decreased Mean Arterial Pressure / Decreased
ECF Volume or NaCl
Renin
(enzyme)
Angiotensinogen
(Plasma Protein)
Angiotensin 1 Angiotensin 2
Angiotensin
Converting Enzyme
Aldosterone
Decreased salt and water
excretion by kidney
Vasoconstrictor
Increased ECF
volume
Renin-Angiotensin-Aldosterone System
Na+ reabsorption and
water conserved
BLOOD

8. MODE OF ACTION IN THE KIDNEYS
Collectin tubules
Principle cell
mineralocorticoid
receptor (MR) protein

9. MODE OF ACTION IN THE KIDNEYS
Collecting tubule
Aldosterone
Principle cell
Basilar membrane
2K
3Na
Na Na Na
K Epithelial membrane

10. Summary

11. FEEDBACK