The filtrate then enters the renal tubule of the nephron. The trimethoprim portion acts to prevent potassium excretion in the distal tubule of the nephron. It is found between afferent arteriole and the distal convoluted tubule of the same nephron. Diseases of the nephron predominantly affect either the glomeruli or the tubules. The juxtaglomerular apparatus is part of the kidney nephron, next to the glomerulus. Some diseases of the nephron predominantly affect either the glomeruli or the tubules. Glomerulopathy is a set of diseases affecting the glomeruli of the nephron. In total this segment accounts for approximately 25-30% of total Na reabsorption along the nephron. A renal corpuscle is the blood-filtering component of the nephron of the kidney. The nephron is the functional unit of the kidney. The kidneys also carry out functions independent of the nephron. In the nephron, osmotic diuretics act at the portions of the nephron that are water-permeable. Glucose is never secreted by a healthy nephron. Common brand names include Asthmanefrin, Micronefrin, Nephron, VapoNefrin, and Primatene Mist.