What is the function of Juxtaglomerular Apparatus?

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Kidneys perform the vital function of throwing out wastes from the body. The various organs associated with it and its whole renal system picks out the wastage and toxic components from the blood selectively and throws it out via excretion process. Urea and uric acid are the by products of metabolism activity, which,  if not drained out from time to time may cause harmful disorders. Whenever the functioning of kidney system is affected the body becomes diseased and treating some of the ailments like kidney failure has still along way to go. Kidney transplants in such cases can give life to the patient in such circumstances.


What is the Juxtaglomerular Apparatus?

The juxtaglomerular apparatus is a type of endocrine organ that is small in size, located within kidneys and helps in the regulating the function of nephrons. This is mainly  involved in the secretion of renin and EPO in response to changes in the renal blood pressure or blood flow.


What is the structure of  Juxtaglomerular Apparatus?

Juxtaglomerular Apparatus are type of epitheloid cells that are located in the afferent arteriole’s media just at the place where it enters glomeruli. These cells of Juxtaglomerular Apparatus embed secretory granules which are limned on the membrane and constitute renin. This renin which is present in the kidney extracts and also the blood stream are generated by JG cells or juxtaglomerular You do not have access to view this node. Renin has also been traced in agarnular lacis cells placed in between the meeting point of afferent and efferent arterioles , but their function here is not yet been ascertained. The point from where the glomerulus makes way for the afferent arteriole and the efferent arteriole move out, the nephron tubule meets the glomerulus arterioles, a place from where it started. The place of starting of distal convolution is adapted area of tubular epithelium known as macula densa. This macula densa is located in close nexus to JG You do not have access to view this node.These JG You do not have access to view this node, macula densa and the lacis cells together constitute the juxtaglomerular apparatus.


What are the functions of Juxtaglomerular Apparatus?

The Juxtaglomerular Apparatus performs the function of adapting glomerular rate of filtration or GFR to distal tubular or NaCl and also aides in the adjusting as well as synthesizing renin release. MD cells or macula densa cells constitute nitric oxide synthase or NOS1 of type 1 isoform. The NO release in the direction of glomerular vasculature is believed to adjust signaling in Juxtaglomerular Apparatus. NOS1 adjustments are accompanied by GFR chronic alterations or tubular NaCl. The NOS1 mRNA molecular characterization displays certain renal variants that suggest specific regulation of cell type at the translation and transcription stage. The Juxtaglomerular Apparatus is placed in an ideal location so that it can supervise the urine amount and composition in nephron as well as blood in afferent arteriole and is known to adjust the renin secretion accordingly.


What is Juxtaglomerular Apparatus composed of?

The Juxtaglomerular Apparatus is made up of:

  • Macula densa which is a part of proximal distal tubule associated with nephron
  • Afferent arteriole which is close to the above nephron
  • Two types of You do not have access to view this node: granular mesangial cells and agranular lacis cells that is present in between the mesangial region’s arteriole and macula densa
  • Granular mesangial cells are composed of prorenin granules that are renin’s precursor and are changed into smooth muscle cells and then go on to store rennin in the afferent arteriole
  • In close nexus to granular cells of Juxtaglomerular Apparatus are sympathetic nerves
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