Natriumkloridkotransportören

Natriumkloridkotransportören, often abbreviated as NKC or NCC, is a protein found in the plasma membrane of various cells, most notably in the distal convoluted tubule of the nephron in the kidney. Its primary function is to reabsorb sodium chloride (NaCl) from the tubular fluid back into the bloodstream. This process is crucial for maintaining electrolyte balance and regulating blood pressure. The transporter works by simultaneously binding and transporting one molecule of sodium ion (Na+) and one molecule of chloride ion (Cl-) across the cell membrane, driven by the electrochemical gradient of sodium.

The activity of the natriumkloridkotransportören is tightly regulated. Hormones like aldosterone, which is released when blood pressure is low, stimulate its activity, leading to increased reabsorption of sodium and water, thereby increasing blood volume and pressure. Conversely, diuretics that target this transporter, known as thiazide diuretics, inhibit its function. By blocking NaCl reabsorption, these drugs increase the excretion of sodium and chloride into the urine, which in turn leads to a decrease in blood volume and blood pressure. This makes them a common treatment for hypertension and edema. Genetic mutations in the gene encoding the natriumkloridkotransportören can lead to rare inherited disorders affecting electrolyte balance and blood pressure regulation.