What is this medullary interstitium . isn't medulla present in brain how did it come to the kidney?? Explain experts

Dear Student

The medulla is a part of the brain. However, the medullary interstitial fluid is present in the kidneys.
The fluid that flows within the tissues present around the loop of Henle of renal medulla is known as medulla interstitial fluid. This fluid helps in absorption of water by increasing hypertonicity.

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