In questa pagina puoi ottenere un'analisi dettagliata di una parola o frase, prodotta utilizzando la migliore tecnologia di intelligenza artificiale fino ad oggi:
In the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the distal tubule, where the distal tubule touches the glomerulus.
The cells of the macula densa are sensitive to the concentration of sodium chloride in the distal convoluted tubule. A decrease in sodium chloride concentration initiates a signal from the macula densa that has two effects: (1) it decreases resistance to blood flow in the afferent arterioles, which raises glomerular hydrostatic pressure and helps return the glomerular filtration rate (GFR) toward normal, and (2) it increases renin release from the juxtaglomerular cells of the afferent and efferent arterioles, which are the major storage sites for renin.
As such, an increase in sodium chloride concentration would result in vasoconstriction of afferent arterioles, and reduced paracrine stimulation of juxtaglomerular cells. This demonstrates the macula densa feedback, where compensatory mechanisms act in order to return GFR to normal.
The release of renin is an essential component of the renin–angiotensin–aldosterone system (RAAS), which regulates blood pressure and volume.