Urinary system Urinary system Assignment Help Living body is made up of all the basic functions that help in their survival and proper functioning. Plants take in minerals and carbon dioxide, giving some useful product and thus excreting all the unused substances or excess substances in the soil. Likewise, human body is remarkably made with all the systems that help in their survival. Digestive, respiratory, reproductive, circulatory, integument, nervous, excretory and many more of other systems functions in human body making is perfect for their survival and growth.
This article has been cited by other articles in PMC. Abstract Tubulo-interstitial fibrosis is a constant feature of chronic renal failure and it is suspected to contribute importantly to the deterioration of renal function.
In the fibrotic kidney there exists, besides normal fibroblasts, a large population of myofibroblasts, which are supposedly responsible for the increased production of intercellular matrix. It has been proposed that myofibroblasts in chronic renal failure originate from the transformation of tubular cells via epithelial—mesenchymal transition EMT or from infiltration by bone marrow-derived precursors.
Little attention has been paid to the possibility of a transformation of resident fibroblasts into myofibroblasts in renal fibrosis.
Therefore we examined the fate of resident fibroblasts in the initial phase of renal fibrosis in the classical model of unilateral ureter obstruction UUO in the rat.
Rats were perfusion-fixed on days 1, 2, 3 and 4 after ligature of the right ureter. The RER became more voluminous, suggesting an increased synthesis of matrix.
Intercellular junctions, a characteristic feature of myofibroblasts, became more frequent. The mitotic activity in fibroblasts was strongly increased.
Renal tubules underwent severe regressive changes but the cells retained their epithelial characteristics and there was no sign of EMT. In conclusion, after ureter ligature, resident peritubular fibroblasts proliferated and they showed progressive alterations, suggesting a transformation in myofibroblasts.
Thus the resident fibroblasts likely play a central role in fibrosis in that model. It has been proposed that fibrosis is not only a response to tubular injury but that it may be the main driving force of nephron loss Remuzzi and Bertani ; Zeisberg et al.
The basic aspects of fibrosis are similar in various organs. The increased accumulation of matrix is associated with a change of the phenotype of interstitial cells. Myofibroblasts are found in addition to or in the place of the quiescent fibroblasts of healthy tissues Liu ; Desmouliere et al.
As discussed in recent reviews myofibroblasts may have different origins, possibly depending on the organ and on the pathology Desmouliere et al. They may originate from the differentiation of resident fibroblasts, from bone-marrow-derived precursors which infiltrate the injured tissue or from transformation of epithelial cells, the so-called epithelial—mesenchymal transition EMT.
The origin of myofibroblasts in the kidney has been the object of intensive research. There is evidence of a role of bone marrow-derived precursors in models of adriamycin nephropathy Li et al. In contrast no significant contribution of such precursors to fibrosis was found in a murine model of unilateral ureter obstruction UUO Roufosse et al.Database of FREE biology essays - We have thousands of free essays across a wide range of subject areas.
Search to find a specific biology essay or browse from the list below: EPO is produced mainly by peritubular fibroblasts of the renal cortex. It is synthesized by renal peritubular cells in adults, with a small amount. The study of the peritubular interstitium in the renal cortex by immunofluorescence takes advantage of the fact that fibroblasts in healthy kidneys of rats and mice strongly express 5′NT in their plasma membrane (Dawson et al.
; Kaissling and Le Hir ). Biology EPO is produced mainly by peritubular fibroblasts of the renal cortex. It is synthesized by renal peritubular cells in adults, with a tiny amount More.
Genetic Rules of Apoptosis and Organ Development The Physiological Healing Process Of Soft Tissue Biology Essay. Peritubular fibroblasts in the renal cortex, hepatocytes and perisinusoidal Ito cells in the liver have recently been identified as the cellular sites of erythropoietin synthesis.
Oct 07, · Here we focus on fibroblasts and specifically on fibroblasts with endocrine function and their biology in health and disease (other articles have extensively reviewed cellular constituents of the immune system within the renal interstitium [9,10]) (Figure 1). On one hand, in cortical nephron renal corpuscle lies in the outer portion of renal cortex whereas in juxamedullary nephron, it lies to the inner side.
The loop of Henle of cortical nephron receives its blood supply from peritubular capillaries whereas in juxamedullary, the loop of Henle receives blood supply from two parts, one is the.