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.
As well, blood in the vasa recta still has large proteins and ions which were not filtered through the glomerulus. This provides an oncotic pressure for ions to enter the vasa recta from the interstitium. The main function of the loop of Henle is to set up a concentration gradient.y means of a countercurrent multiplier system, which utilizes electrolyte pumps, the loop of Henle creates an area of high urea concentration deep in the medulla, near the papillary duct in the collecting duct system.