Funcion de la macula densa pdf files

A macula densa e porcao final do ramo ascendente espesso e apos ela, iniciase o tubulo contorcido distal. The macula densa cells are a small subset of approximately 20 cells per nephron at the distal end of the ctal of the loop of henle. The cells of the macula densa are sensitive to the concentration of sodium chloride in the distal convoluted tubule. Macula densa definition of macula densa by medical dictionary. Tgf, a major mechanism by which gross filtrationabsorption mismatches are prevented, is the subject of the article by thomson et al. The cells of the macula densa are taller and have more prominent nuclei than surrounding cells of the distal straight tubule cortical thick ascending limb the close proximity and prominence of the nuclei cause this segment of the distal tubule wall to appear darker in microscopic preparations, hence the name macula densa. The juxtaglomerular apparatus also known as the juxtaglomerular complex is a structure in the kidney that regulates the function of each nephron, the functional units of the kidney. This is due to reduced filtration by the glomerulus. Laldosterone agit sur le metabolisme des electrolytes. In addition to tubular salt sensing, macula densa cells also sense alterations in tissue metabolism through the accumulation of the krebs cycle intermediate, succinate, in tubular fluid. As shown schematically in figure figure1, 1, in every mammalian nephron, the distal tubule is attached to its glomerulus of origin at a point where normally about 80% of the filtered water and 85.

These cells are in close approximation to the juxtaglomerular vascular smooth muscle cells of the afferent arterioles of their glomeruli, and together they form what is known as the juxtaglomerular apparatus. What is the function of the macula densa cells of the. The juxtaglomerular apparatus is named because it is next to juxta the glomerulus. The macula densa is the thickening where the distal tubule touches the glomerulus the cells of the macula densa are sensitive to the concentration of sodium chloride in the. The cells on the side of the tubule facing the glomerulus have a distinct appearance and constitute the macular densa figure 1. Macula densa definition of macula densa by the free dictionary. The macula of the utricle, or utricular macula is the region of the utricle that receives the utricular filaments of the vestibulocochlear nerve. In the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the distal tubule at the point of return of the nephron to the vascular pole of its parent glomerulus, glomerular vascular pole. In 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. These cells sense the nacl content of the tubule and make changes to gfr appropriately. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Macula densa definition of macula densa by medical. The macula densa is worth its salt pubmed central pmc.

Aparelho justaglomerular wikipedia, a enciclopedia livre. Macula densa sensing and signaling mechanisms of renin release. The juxtaglomerular apparatus consists of three types of cells. A decrease in blood pressure results in a decreased concentration of sodium and chloride ions at the macula densa. In the kidney, the macula densa is an area of closely packed specialized cells lining the wall of the thick ascending limb of henle talh at the point of return of the nephron to the vascular pole of its parent glomerulus glomerular vascular pole the cells of the macula densa are sensitive to the ionic content and water volume of the fluid in the talh, producing molecular signals that. Halperin md, frcpc, in fluid, electrolyte and acidbase physiology fifth edition, 2017. Oct 03, 2017 the tubuloglomerular feedback mechanism of renal autoregulation is the key function of the macula densa. Tratamiento del agujero macular american academy of. These cells are in close approximation to the juxtaglomerular vascular smooth. Oct 15, 1999 macula densa cells express high levels of nosi, the neuronal isoform of nitric oxide synthase, and are a likely source of no acting in the jga 19, 20. Dal punto di vista morfologico essa rappresenta il punto di passaggio fra il segmento rettilineo e quello convoluto del tubulo distale.