High resolution

Module 7: Figure juxtaglomerular apparatus

Structural organization of the juxtaglomerular apparatus (JGA).

Each kidney glomerulus has a juxtaglomerular apparatus (JGA) consisting of different cells that interact with each other to regulate the flow of blood through the glomerulus (white arrows). A band of smooth muscle cells control the flow of blood that enters through the afferent arteriole and leaves via the efferent arteriole. The NaCl level within the distal convoluted tubule is monitored by the macula densa cells that send stimuli to adjust the activity of smooth muscle cells, which control blood flow through the afferent arterioles. The intraglomerular mesangial cells control blood flow through the glomerular arterioles. The renin-producing granular cells release renin as part of the renin–angiotensin system (RAS). The mauve arrow illustrates the ultrafiltration pathway while the double-headed red arrows illustrate the cells that are connected via gap junctions.