How does macula densa sense NaCl?

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Macula densa cells can sense variations in tubular fluid composition, including salt content and metabolites such as succinate. Salt is sensed via the NKCC2 and NHE2, whereas tubular succinate triggers the metabolic receptor GPR91 at the luminal plasma membrane.

How does macula densa respond to high sodium?

In response to elevated sodium, the macula densa cells trigger contraction of the afferent arterioleafferent arterioleThe afferent arterioles are a group of blood vessels that supply the nephrons in many excretory systems. They play an important role in the regulation of blood pressure as a part of the tubuloglomerular feedback mechanism. Afferent arterioles. Scheme of renal tubules and its vascular supply.https://en.wikipedia.org › wiki › Afferent_arteriolesAfferent arterioles – Wikipedia, reducing flow of blood to the glomerulus and the glomerular filtration rate.

Does macula densa sense Na or Cl?

Macula densa cells sense luminal NaCl concentration via furosemide sensitive Na+2Cl-K+ cotransport. Pflugers Arch.

What is macula densa NaCl?

Functionally, the macula densa serves as a sensor of luminal NaCl. Concentration-dependent salt uptake through the Na-K-2Cl cotransporter in the apical membrane of macula densa cells initiates a sequence of events that regulates afferent arteriolar tone and thereby filtration rate (10).

What is the role of the macula densa?

What does the macula densa detect?

Macula densa cells detect changes in luminal sodium chloride concentration through a complicated series of ion transport–related intracellular events.

How does NaCl concentration affect NFP and therefore GFR?

Sodium concentration in the filtrate increases when GFR increases; it will decrease when GFR decreases. To excrete more Na+ in the urine, increase the flow rate. Net filtration pressure (NFP) = glomerular blood hydrostatic pressure (GBHP) – [capsular hydrostatic pressure (CHP) + blood colloid osmotic pressure (BCOP).

What do macula densa cells respond to?

It is thought that the macula densamacula densaIn the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the distal tubule, at the point where the thick ascending limb of the Loop of Henle meets the distal convoluted tubule. The macula densa is the thickening where the distal tubule touches the glomerulus.https://en.wikipedia.org › wiki › Macula_densaMacula densa – Wikipedia cells are sensory cells that respond to the sodium concentration in the fluid within the distal tubule and, perhaps, to the rate of fluid flow past them.

What does macula densa cells respond to?

On the other hand, increased levels of sodium chloride in the tubular filtrate are caused by increased blood pressure. Macula densa cells detect this high blood pressure and respond to it by two mechanisms: vasoconstriction of the afferent arteriole and decreased release of renin from juxtaglomerular cells.

What is secreted by macula densa?

The macula densa, in response to the change in the Na concentration in the distal tubulesdistal tubulesThe distal convoluted tubule (DCT) is a portion of kidney nephron between the loop of Henle and the collecting tubule. Distal convoluted tubule. Kidney nephron (“1st proximal convoluted tubule”, “2nd distal convoluted tubule”) Section of cortex of human kidney.https://en.wikipedia.org › wiki › Distal_convoluted_tubuleDistal convoluted tubule – Wikipedia, signals the juxtaglomerularjuxtaglomerularThe juxtaglomerular apparatus is the location of renin-secreting cells and the macula densa and lies at the junction between the loop of Henle and the distal nephron at which the tubule comes in close proximity to the afferent arteriole.16.https://www.sciencedirect.com › juxtaglomerular-apparatusJuxtaglomerular Apparatus – an overview | ScienceDirect Topics cells to release renin. Renin is stored in granules and the secretion is stimulated by the β-adrenergic response and cAMP augmentation.

Which protein is involved in a macula densa?

Specifically, these included both classic and recently identified MD-specific proteins such as cyclooxygenase 2, microsomal prostaglandin E2 synthase 1, and pappalysin 2.

How does macula densa affect GFR?

Increased sodium chloride delivery to the macula densa causes release of adenosine, which then binds to the afferent arteriole causing vasoconstriction. This vasoconstriction subsequently decreases GFR. The opposite response occurs because of decreases in sodium chloride delivery to the macula densa.

What does a high concentration of NaCl in the renal tubule at the Juxtaglomerular apparatus JGA most likely indicate?

High NaCl concentration in the filtrate at the JGA indicates that GFR is too high. By decreasing the diameter of the arteriole delivering blood to the glomerulus, HPg is decreased, resulting in lower GFR.

What does the macula densa comprise of?

The juxtaglomerular apparatus comprises afferent and efferent arterioles, complemented by granular, renin-secreting cells, the macula densa, a specialized group of distal tubular cells and lacis cells (Goormaghtigh cells, polar cushion, extraglomerular mesangial cells).

What do the macula densa cells regulate?

Macula densa cells monitor intratubular salt concentrations to regulate renal blood flow via afferent arteriole constriction and dilation. The juxtaglomerular cells also contain renin granules, which can send out a wider signal to control vascular resistance through the renin-angiotensin-aldosterone pathways.

What is function of macula densa?

What do macula densa cells regulate?

What do the macula densa cells detect?

Which of the following structure is part of macula densa?

So, the correct answer is ‘Distal convoluted tubule’.

What is the function of the macula densa cells of the juxtaglomerular complex?

Its function is to sense sodium chloride concentration in the filtrate and activate tubuloglomerular feedback which adjusts GFR to regulate the concentration of tubular sodium and chloride. Juxtaglomerular cells secrete renin in response to macula densa cells, in case of high blood pressure.

What is the role of the macula densa cells?

What do macula densa cells produce?

Macula densaMacula densaIn the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the distal tubule, at the point where the thick ascending limb of the Loop of Henle meets the distal convoluted tubule. The macula densa is the thickening where the distal tubule touches the glomerulus.https://en.wikipedia.org › wiki › Macula_densaMacula densa – Wikipedia cells produce prostaglandins as long as sodium levels are low. These prostaglandins stimulate the release of renin from juxtaglomerular cellsjuxtaglomerular cellsJuxtaglomerular cells (JG cells), also known as granular cells are cells in the kidney that synthesize, store, and secrete the enzyme renin. They are specialized smooth muscle cells mainly in the walls of the afferent arterioles (and some in the efferent arterioles) that deliver blood to the glomerulus.https://en.wikipedia.org › wiki › Juxtaglomerular_cellJuxtaglomerular cell – Wikipedia. Then renin – angiotensin – aldosterone system (RAAS) begins as a part of tubuloglomerular feedback mechanism.