1 Strenuous exercise, such as running a marathon, can also cause blood in the urine. 2  White blood cells may be a sign of infection or kidney disease. 3  Casts. 4  Some types of kidney disease can cause plugs of material (called casts) to form in tiny tubes in the kidneys.
Top 10 facts about the world. The loop of Henle is a part of a nephron, a tiny tube inside the kidneys that filters solutes. Each kidney contains hundreds of thousands of individual nephrons, which pass between the cortex of the kidneys and the medulla, connecting to collecting ducts which route urine to the ureter so that it can be expressed.
Pump: The Na+/K+/2Clâ transporter in the ascending limb of the loop of Henle helps to create a gradient by shifting Na+ into the medullary interstitium. The thick ascending limb of the loop of Henle is the only part of the nephron lacking in aquaporinâa common transporter protein for water channels.