- What podocytes are and their function?
- What is JGA?
- What should not be found in filtrate?
- What do Extraglomerular mesangial cells produce?
- What are mesangial cells and how do they affect filtration at the glomerulus?
- What is mesangial Hypercellularity?
- What stimulates JG cells?
- What is the mesangial matrix?
- What happens when mesangial cells contract?
- Where is JGA located?
- What happens during tubular reabsorption?
- What is the function of mesangial cells?
- What is the function of Juxtaglomerular cells?
- What activates Juxtaglomerular cells?
- What are mesangial cells and podocytes?
What podocytes are and their function?
Podocytes play an important role in glomerular function.
Together with endothelial cells of the glomerular capillary loop and the glomerular basement membrane they form a filtration barrier.
Podocytes cooperate with mesangial cells to support the structure and function of the glomerulus..
What is JGA?
The juxtaglomerular apparatus is a specialized structure formed by the distal convoluted tubule and the glomerular afferent arteriole. It is located near the vascular pole of the glomerulus and its main function is to regulate blood pressure and the filtration rate of the glomerulus.
What should not be found in filtrate?
Blood proteins and blood cells are too large to pass through the filtration membrane and should not be found in filtrate. Tubular reabsorption begins in the glomerulus.
What do Extraglomerular mesangial cells produce?
The specific function of extraglomerular mesangial cells is not well understood, although it has been associated with the secretion of erythropoietin and secretion of renin.
What are mesangial cells and how do they affect filtration at the glomerulus?
Mesangial cells provide structural support to the glomerular tuft, produce and maintain mesangial matrix, communicate with other glomerular cells by secreting soluble factors, and may contribute to the glomerular capillary flow via their contractile properties. Figure 22.11.
What is mesangial Hypercellularity?
”Mesangial hypercellularity” was defined as presence of more than three mesangial cells in the mesangial field. 6 Immunofluorescence examination was performed using anti- bodies specific for human IgG, IgA, IgM, C3, C1q, fibrinogen and albumin. All the patients with mesangial proliferation were included.
What stimulates JG cells?
Juxtaglomerular cells secrete renin in response to a drop in pressure detected by stretch receptors in the vascular walls, or when stimulated by macula densa cells. … When stimulated by epinephrine or norepinephrine, these receptors induce the secretion of renin.
What is the mesangial matrix?
Mesangial cells lie close to the capillary lumen and play an important role in glomerular hemodynamics and immune complex clearance. The mesangial cells produce a matrix made up of collagen, fibronectin, and proteglycans that supports the glomerular capillaries.
What happens when mesangial cells contract?
Contraction of mesangial cells is coupled with contraction of the basement membrane of the endothelium of glomerular capillaries. This causes a decrease in surface area of the basement membrane and thus a decreased glomerular filtration rate.
Where is JGA located?
glomerulusThe JGA is located at the vascular pole of the glomerulus, where a portion of the distal nephron comes into contact with its parent glomerulus.
What happens during tubular reabsorption?
Tubular reabsorption is the process that moves solutes and water out of the filtrate and back into your bloodstream. This process is known as reabsorption, because this is the second time they have been absorbed; the first time being when they were absorbed into the bloodstream from the digestive tract after a meal.
What is the function of mesangial cells?
The extraglomerular mesangial cells are adjacent to the intraglomerular mesangial cells that are located inside the glomerulus and in between the capillaries. The primary function of mesangial cells is to remove trapped residues and aggregated protein from the basement membrane thus keeping the filter free of debris.
What is the function of Juxtaglomerular cells?
The afferent arteriole in this region contains specialised secretory cells (smooth muscle cells) called juxtaglomerular cells, that secrete renin. These cells do two things: They monitor blood pressure, by measuring how much the arteriole wall is stretched.
What activates Juxtaglomerular cells?
Juxtaglomerular Cells Although they are activated by prostaglandins released from the macula densa cells, they can also release renin independently of the macula densa. Baroreceptors found in the arterioles trigger renin secretion if there is a fall in blood pressure in the arterioles.
What are mesangial cells and podocytes?
Mesangial cells and their matrix form the central stalk of the glomerulus and are part of a functional unit interacting closely with endothelial cells and podocytes. Alterations in one cell type can produce changes in the others.