Which protein is produced by the renal tubules and found in urine?

Uromodulin, also known as Tamm-Horsfall protein, is the protein produced by the renal tubules and is found in urine. This glycoprotein is secreted primarily by the epithelial cells of the thick ascending limb of the loop of Henle. Uromodulin plays a significant role in urinary function, such as helping to prevent urinary tract infections by inhibiting the adherence of bacteria to the urothelium, and in regulating electrolyte balance and calcium homeostasis in the renal system.

Albumin, on the other hand, is a protein that is typically found in the blood. While small amounts can appear in urine under normal conditions, significant amounts in urine may suggest a pathological condition, such as kidney disease. Globulin includes a group of proteins found in blood serum that are usually not produced by the renal tubules. Hemoglobin is primarily found in red blood cells and its presence in urine usually indicates hemolysis or bleeding within the urinary tract, rather than a normal secretion by the renal tubules. Thus, it is uromodulin that is specifically recognized as being produced by the renal tubules and present in normal urine.