3. ๏ฎ Anatomical considerations of renal system
๏ฎ Function of renal system
๏ฎ Nephron (structure and Types)
๏ฎ Renal blood vessel
๏ฎ Renal Blood Flow (RBF)
Contents
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Dr.Mohand Hassan Moalla 2017
4. Anatomical consideration of renal system
๏ฎ The urinary system consists of
๏ฎ The paired kidneys
๏ฎ The paired ureters
๏ฎ The unpaired bladder
๏ฎ Urethra
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Dr.Mohand Hassan Moalla 2017
6. Function of renal system
๏ฎ Regulation of Water and Electrolyte Balance
๏ฎ Excretion of Metabolic Waste
๏ฎ Regulation of Arterial Blood Pressure
๏ฎ Regulation of Red Blood Cell Production
๏ฎ Regulation of Vitamin D Production
๏ฎ Play important role Regulation of pH
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10. Nephron (structure and Types)
๏ฎ The functional units of the kidney are nephrons
๏ฎ Each kidney contains approximately 1 million
nephrons
๏ฎ A nephron consists of a glomerulus and a renal
tubule
๏ฎ The glomerulus is a glomerular capillary
network
๏ฎ The glomerular capillaries are surrounded by
Bowman's capsule (or Bowman's space)
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11. ๏ฎ Renal tubule comprises the following
segments (beginning with Bowman's space):
1. Proximal convoluted tubule (PCT)
2. The loop of Henle (which contains
descending and ascending limb)
3. Distal convoluted tubule (DCT)
4. Collecting ducts
Nephron (structure and Types)
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12. ๏ฎ There are two types of nephrons
according to the location of their glomeruli
and length of loops of Henle:-
1. superficial cortical nephrons
2. juxtamedullary nephrons
Nephron (structure and Types)
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14. ๏ฎ The superficial cortical nephrons have their
1. glomeruli in the outer cortex
2. These nephrons have relatively short loops of
Henle
๏ฎ The juxtamedullary nephrons have their
1. glomeruli near the corticomedullary border
2. These nephrons have relatively long loops of
Henle
Nephron (structure and Types)
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Dr.Mohand Hassan Moalla 2017
15. Renal Blood Supply
๏ฎ Blood reaches the kidneys through the renal arteries
๏ฎ They are short and come directly from abdominal
aorta
๏ฎ The renal arteries divide into progressively smaller
branches:
1. Interlobar artery
2. arcuate artery
3. interlobular arteries
4. afferent arterioles
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17. RENAL Blood vessel
๏ฎ The afferent arterioles deliver blood to the glomerular
capillaries
๏ฎ Blood leaves the glomerular capillaries via the
efferent arterioles
๏ฎ The efferent arterioles deliver blood to the:-
1. peritubular capillaries:- (superficial cortical
nephrons) surround the nephrons
2. vasa recta:- (juxtamedullary nephrons )vessels that
form hairpin loops alongside the loops of Henle
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23. Renal Blood Flow
๏ฎ The kidneys receive about 25% of the cardiac output
(COP)
๏ฎ (COP) 5 L/min --------------๏ 100%
๏ฎ (RBF) renal blood flow -----------๏ 25%
๏ฎ (RBF) = 1.25 L/min (highest of all the organ systems)
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24. Chemical massagers (hormones)
NE Dopamine Angiotensin II Prostaglandins Acetylcholine
constriction Dilatation constriction Dilatation Dilatation
Interlobular A
afferent. A
Efferent. A
afferent.A afferent. A
Efferent. A
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33. ๏ฎ To calculate the renal blood flow , we use the
ratio of plasma to whole blood .
๏ฎ The PCV (RBCs%) is about 45% therefore if
plasma constitutes 55% of blood volume,
blood flow can be calculated as follows
๏ฎ RBF = 700 X 100 = 1273ml/min
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Measurement of renal blood flow
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