Kidney Flashcards
What can periodontitis contribute to
Chronic inflammation in the body
What are the kidneys
Excretory organs
They process blood and rot the body of the waste products of metabolism via urine
What is a main function of the kidneys
To maintain the internal homeostasis of fluid
Explain how the kidneys play an important role in maintaining blood pressure
They control levels of fluid and electrolytes such as sodium in the blood
What role do the kidneys play in red blood cell formation
They secrete the hormone erythropoietin which signals to the red bone marrow to produce red blood cells s
What is included in the anatomy of the urinary system
- two kidneys (produce urine)
- ureters (conveys urine)
- bladder (stored)
- urethra (void urine)
Where do the kidneys lie
Lie behind the peritoneal cavity they are encased in renal fat pad
What are the three distinct part of the kidneys
- cortex
- medulla
- pelvis
What is the function of the cortex
Contains 85% of all kidney tubules (nephrons)
What is the function of the medulla
The site where urine is concentrated
Prevents excess water loss
What is the function of the pelvis
Collection area for urine which is funnelled into the ureter
What artery supplies the kidneys
The renal artery delivers blood from the abdominal aorta
How much blood is processed per minute in the kidneys
Process 1.2 litres blood per minute (1/5 cardiac output)
Name the blood vessels of the kidneys
- renal artery
- segmental arteries
- lobar arteries
- interlobular arteries
- arcuate arteries
- interlobular arteries
Describe the blood flow after the interlobular arteries
> afferent arterioles > globular capillaries > efferent arterioles > pertitubular capillaries (vasa recta) > interlobular veins
What is a nephron
The nephron is the basic functional unit of the kidney
What is the function of the nephron
Structured optimally evolved to filter blood plasma…
And excrete waste products in the metabolism in urine
- cortical nephrons
- juxtamedullary nephrons
Name the different parts of the nephron
- glomerus
- bowman’s capsule
- proximal convoluted tubule
- loop of Henle
- distal convoluted tubule
- collecting tubule
To ureter
What is the direction of blood flow in the nephron
Glomerulus > bowman’s capsule > proximal convoluted tubule > loop of henle > distal convoluted tubule > collecting duct
What parts of the nephron are responsible for filtration
Glomerus
Bowman’s capsule
What is included in the renal corpuscle
- glomerus
- bowman’s capsule
What is the renal tubule composed of
-proximal convoluted tubule
-loop of henle
-distal convoluted tubule
-collecting duct
What is the glomerulus
- a network of fine capillaries
- a single layer of endothelial cells resting on a basement membrane
- Fenestrated
- enables rapid filtration of blood plasma
- surrounded by bowman’s capsule
What is bowmans capsule
- a cup like structure surrounding the glomerulus
What is bowmans space filled with
Filtered from the blood is collected in the nephron
What is the parietal outer layer
simple squamous epithelium
What is the visceral (inner) layer comprised of
comprised of specialised epithelium
What are the long branched processes that wrap around the glomerular capillaries called
Pedicels of podocytes
What forms the filtration barrier
The glomerular endothelium, basement membrane and pedicels form the filtration barrier
Describe the filtration barrier
Pedicels share basement membrane with the Fenestrated endothelium
The filtration barrier freely permeable to water and small molecules but not large proteins or cells
What determines which molecules are filtered
Size and charge of filtration
What is the first step in blood processing called
Glomerular filtration
Describe the process of glomerular filtration
1) unfiltered blood arrives at the glomerulus via and the afferent arteriole
2) blood components filtered through the filtration barrier
3) filtered blood exits the glomerulus via the efferent arteriole
What is filtered in the blood
- sodium
- chloride
- calcium
- phosphate
- potassium
- bicarbonate
- water
- glucose
- amino acids
- urea
- creatinine
What is not filtered in the blood
- negatively charged proteins (albumin)
- cells, large proteins (haemoglobin)
Glomerular filtration rate (GFR)
- the rate at which blood is filtered through the glomerulus into bowmans capsule
Glomerular filtration rate (GFR)
- primarily driven by glomerular hydrostatic pressure
- counteracted by hydrostatic pressure in the Bowmans capsule
- counteracted by glomerular osmotic pressure
What is the Glomerular filtration rate (GFR)
The rate at which blood is filtered through the glomerulus into the bowman’s capsule
What is glomerular filtration rate (GFR)
The rate at which blood is filtered through the glomerulus into the bowman’s capsule
What is GFR influenced by
Influenced by many factors :
- hydrostatic pressure
- osmotic pressure
- systemic blood pressure
- renin-angiotensin system
- disease
What is a normal healthy GFR
125ml/min
GFR = …
Kidney function
Reduced GFR =
Inefficient blood clearance and waste removal
What indicates kidney problems
Measuring serum creatinine higher than expected it may indicate the filtration rate isn’t working hence kidney problems
Describe stage 1 kidney function
Normal
90% or higher
Stage 2 kidney function
Mild loss of kidney function
60-89% function
Stage 3a kidney function
Mild to moderate loss of kidney function
Stage 3b kidney function
Moderate to severe
44%-30% function
Stage 4 kidney disease
Severe
15-29%
Stage 5 kidney disease
Kidney failure less than 15% function
