Juxtaglomerular Cells (AfA)

Juxtaglomerular cells (JCs) are specialized smooth muscle cells located in the wall of the afferent arteriole, which supplies blood to the nephron. The cells are round, plump, and epithelioid in nature. JCs synthesize and release renin from storage granules. Renin is a hormone that initiates the enzymatic cascade that generates angiotensin, which, in turn, plays a role in blood pressure regulation, renal hemodynamics, and electrolyte balance. Adult JCs also contain actin myofilaments, peroxisomes, small electron-dense vesicles, and few mitochondria. They are connected to arteriolar smooth muscle cells, endothelial cells, and other JC cells by gap and myoendothelial junctions.