Nephron Anatomy
In order to understand the problems that a kidney disease can cause you must first understand what a health kidney should be like.
(Slagter - drawing anatomy of kidney, Nephron and glomerulus - no labels)
Where is the Nephron located and what does it do?
There are millions of nephrons that work to filter your blood in the kidney. The nephrons can be found in both the cortex and the medulla of the kidney. Without the nephron the kidney would not be able to filter your blood. The 4 main functions of the nephron being:
1. Filtration
2. Reabsorption
3. Secretion
4. Excretion
What are the different parts of the Nephron and what do they do?
We first start in the bowman's capsule which has the glomerulus and the afferent and efferent arteriole and makes the filtrate.
​​
The afferent arteriole brings in the unfiltered blood to the glomerulus and the efferent arteriole carries the blood away from the glomerulus.
​
The glomerulus is like a sieve. Where the unfiltered blood, is filtered and enters the Bowmans capsule due to the blood pressure. The filtered blood that enters the Bowmans is called the filtrate.
​
The filtrate is made up of:
- water
- Glucose
- Amino acids
- Salts
- different ions
- meds (if applicable)
- urea
​​
The proximal tubule is the a part of the nephron that filtrate goes through after the glomerulus and it reabsorbs essential elements and water from the filtrate.
​
Loop of henle:
- The descending limb of the loop of henle is where aquaporins allow for majority of the water to be reabsorbed into the interstitial fluid (water exits the the filtrate).
​
- The ascending limb of the loop of Henle and the proximal part of distal tubule is where essential elements like sodium, potassium, chloride, bicarbonate etc. are reabsorbed and the filtrate is also diluted.
​
The collecting duct of the distal tubule contributes to the acid base regulations of the body. Many of the substances are secreted into the filtrate. These include H+ ions, Ammonium and potassium.
​
The collecting duct is where filtrate becomes urine. NaCl and water can be reabsorbed. How much water is absorbed is based on how much water someone drinks and hormonal regulation.
