Juxtaglomerular apparatus

The juxtaglomerular apparatus is in the nephron, the functional unit of the kidney, the contact point between versorgendem blood vessel ( afferent ) and the distal renal tubule. Here, the key to control of electrolyte and water balance and blood pressure enzyme renin is formed, among others, which is then transported through the vascular system to the liver (→ renin -angiotensin -aldosterone system ).

The juxtaglomerular apparatus is composed of three parts:

• The macula densa is a chemo -sensitive field, which consists of high dense epithelial cells in the wall of the coiled distal tubule of a renal tubule.
• Termed Polkissen, renin -containing ( granulated ) epithelioid myocytes (ie lying in the epithelium muscle cells), which also appear under the term juxtaglomerular cells in the wall of the afferent.
• Extraglomeruläre mesangial cells or sentinel cells are enclosed by afferent, efferent arteriole, and to find the macula densa.

The Polkissen together with the extraglomerular mesangial the vasoactive enzyme renin.