Wiktionary
juxtaglomerular apparatus
n. (context physiology English) A minuscule structure inside the kidney, involved in the regulation of the activity of each nephron.
Wikipedia
Juxtaglomerular apparatus
The juxtaglomerular apparatus is a microscopic structure in the kidney that regulates the function of each nephron, the functional units of the kidney. The juxtaglomerular apparatus is named because it is next to (juxta-) the glomerulus.
The juxtaglomerular apparatus consists of three cells:
- the macula densa, a part of the distal convoluted tubule of the same nephron
- juxtaglomerular cells, which secrete renin
- extraglomerular mesangial cells