Chapter 11: Urinary system
Distal convoluted tubule
The distal convoluted tubule (DCT) is composed of simple cuboidal epithelium. The DCT is located in the cortex and corticomedullary junction. The functions of this segment include fine-tuning ion concentrations and acid-base balance to maintain homeostasis. The epithelium of the DCT is also involved in reabsorption or excretion of bicarbonate and hydrogen ions to maintain blood pH. It can secrete potassium into the tubular lumen under the influence of the hormone aldosterone and reabsorb calcium in response to parathyroid hormone.