What is tubular secretion? What are some examples of substances secreted through the renal tubules?
Tubular secretion is the passage of substances from the blood capillaries that surround the nephron tubules to the tubular lumen for these substances to be excreted with urine. Ammonia, uric acid, potassium, bicarbonate and hydrogen ions, metabolic acids and bases, various ingested drugs (medicines) and other substances are secreted by the nephron tubules.
