What is the macula densa & What is its function?
What is the macula densa & What is its function?
Macula densa (MD) cells are chief cells within the kidney, playing key sensory and regulatory functions in the maintenance of body fluid, electrolyte homeostasis, and blood pressure.
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 activates macula densa?
The macula densa, in response to the change in the Na concentration in the distal tubules, signals the juxtaglomerular cells to release renin. Renin is stored in granules and the secretion is stimulated by the β-adrenergic response and cAMP augmentation.
What are the 3 components of the juxtaglomerular?
The main components of the JGA are the macula densa of the thick ascending limb, the renin-producing granular cells of the afferent arteriole, and the extraglomerular mesangial cell (Goormaghtigh cell, lacis cell; Figure 47.3).
What do the macula densa cells regulate in the role as part of the Tubuloglomerular feedback loop?
What do macula densa cells regulate? Cells of macula densa regulate the tubular sodium-chloride concentration by tubuloglomerular feedback mechanism and renal blood flow by myogenic mechanism that involves vasoconstriction and vasodilation.
Does the macula densa secrete renin?
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….
| Macula densa | |
|---|---|
| FMA | 86333 |
| Anatomical terminology |
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 is the function of the macula densa cells of the juxtaglomerular complex JGC )?
What is the function of the macula densa cells of the juxtaglomerular complex (JGC)? The macula densa cells monitor the NaCl content of the filtrate entering the distal convoluted tubule.
What is the function of the macula densa cells of the Juxtaglomerular Complex JGC )?
How does tubuloglomerular feedback regulate GFR?
Tubuloglomerular feedback results in the regulation of GFR. A drop in arterial blood pressure causes both a decrease in GFR and a decrease in renal blood flow. The drop in GFR causes a tubuloglomerular feedback—mediated arteriolar dilation, restoring GFR and also increasing renal blood flow.
Are macula densa cells Baroreceptors?
The renal baroreceptor monitors renal perfusion pressure and signals an increase in renin when renal perfusion pressure falls. In the macula densa mechanism, macula densa cells sense the decrease in chloride ions in the filtrate in the distal tubule, thereby stimulating release of renin.