Question

Explain what would happen to the function of the kidney if the Loop of Henle began to shrink? Specifically, describe (with justification) what would happen to reabsorption capabilities of the kidney? (4 marks) Describe what would happen to the countercurrent mechanism and the ability to concentrate urine (with justification)?

Answer 1

Main function of loop of henle is reabsorption of water and salts and set up a concentration gradient, if the loop of henle begins to shrink, than the loop of henle would not function properly because of which  significant portion of reabsorption of water and ions would not happen as a result the urine would be dilute and loss of useful ions along with water would occur. Overall the loop of Henle reabsorbs around 25% of filtered ions which are mainly sodium, potassium, calcium, bicarbonate, etc and 20% of the filtered water in a normal kidney, this condition can limit the amount of water and important ions needed for the body, which can cause significant damage to the body.

The loop of henle have important characteristics that enable countercurrent multiplication, countercurrent multiplication in the loops of Henle of juxtamedullary nephrons is largely responsible for developing the osmotic gradients that are needed to concentrate urine, so if the loop of henle do not function properly, the concentration gradient would not be established and the mechanism of counter current multiplication would not occur because of which concentration of urine do not take place as a result urine will be very dilute.

Note : The length of the loop of Henle determines the size of the gradient , the longer the loop, the greater the osmotic gradient. Urea recycling in the inner medulla also contributes to the osmotic gradient generated by the loops of Henle.