Macula densa

Definition

The macula densa is a group of specialized cells located in the distal convoluted tubule of the nephron in the kidneys, which senses sodium chloride (NaCl) concentration and regulates blood pressure and volume by signaling the juxtaglomerular cells to release renin. These cells play a crucial role in the kidney's ability to regulate blood pressure and filtrate formation through feedback mechanisms.

Related terms

Nephron:

The functional unit of the kidney that filters blood to produce urine, consisting of a glomerulus and its associated tubules.

Juxtaglomerular Cells: Specialized cells located around the glomerulus that release renin in response to signals from the macula densa, playing a key role in regulating blood pressure.

Renin:

An enzyme secreted by juxtaglomerular cells which plays an important role in the body's renin-angiotensin system (RAS), affecting blood pressure and electrolyte balance