Question: What Are Podocytes Made Of?

What type of cells are podocytes?

There are therefore four resident cell types in the glomerulus: endothelial cells, mesangial cells, parietal epithelial cells of Bowman’s capsule, and podocytes (Figure 1a).

Podocytes are pericyte-like cells with a complex cellular organization consisting of a cell body, major processes, and foot processes (FPs)..

What is the shape of nephron podocytes?

It transitions onto the glomerular capillaries in an intimate embrace to form the visceral layer of the capsule. Here, the cells are not squamous, but uniquely shaped cells (podocytes) extending finger-like arms (pedicels) to cover the glomerular capillaries (Figure 1). Figure 1.

Why do podocytes not undergo mitosis?

The podocytes are arrested at G0 of the cell cycle. If podocytes frequently underwent mitosis, it would alter the number and therefore the size of the fenestrations on the Bowman’s capsule, changing the ultrafiltration rate.

What are podocytes?

Podocytes are specialized epithelial cells that cover the outer surfaces of glomerular capillaries. Unique cell junctions, known as slit diaphragms, which feature nephrin and Neph family proteins in addition to components of adherens, tight, and gap junctions, connect adjacent podocyte foot processes.

Why is it called Bowman’s capsule?

Bowman’s capsule is named after Sir William Bowman (1816–1892), a British surgeon and anatomist. However, thorough microscopical anatomy of kidney including the nephronic capsule was first described by Ukrainian surgeon and anatomist from the Russian Empire, Prof.

What’s the glomerulus?

The glomerulus is a tuft of capillaries located within Bowman’s capsule within the kidney. … Blood enters the capillaries of the glomerulus by a single arteriole called an afferent arteriole and leaves by an efferent arteriole.

Where are podocytes found?

Podocytes are found lining the Bowman’s capsules in the nephrons of the kidney. The foot processes known as pedicels that extend from the podocytes wrap themselves around the capillaries of the glomerulus to form the filtration slits.

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.

What is the Bowman’s capsule?

Bowman’s capsule is a part of the nephron that forms a cup-like sack surrounding the glomerulus. Bowman’s capsule encloses a space called “Bowman’s space,” which represents the beginning of the urinary space and is contiguous with the proximal convoluted tubule of the nephron.

What does macula densa sense?

Macula densa cells sense changes in sodium chloride level, and will trigger an autoregulatory response to increase or decrease reabsorption of ions and water to the blood (as needed) in order to alter blood volume and return blood pressure to normal.

What is a Juxtaglomerular apparatus?

The juxtaglomerular apparatus is the location of renin-secreting cells and the macula densa and lies at the junction between the loop of Henle and the distal nephron at which the tubule comes in close proximity to the afferent arteriole.16.

Do podocytes have a nucleus?

Podocytes show a flat cytoplasm with a visible rise containing the nucleus. They have a well-developed Golgi apparatus, abundant endoplasmic reticulum, and many mitochondria and lysosomes. The cytoplasm sends many tiny finger-like protrusions that wrap the basal lamina of capillaries.

What is the purpose of podocytes?

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 are the Vasa recta?

The vasa recta, the capillary networks that supply blood to the medulla, are highly permeable to solute and water. … The ability of the vasa recta to maintain the medullary interstitial gradient is flow dependent. A substantial increase in vasa recta blood flow dissipates the medullary gradient.

What is podocyte injury?

The visceral glomerular epithelial cell, also called podocyte, is a terminally differentiated cell that lines the outer aspect of the glomerular basement membrane (GBM). It therefore forms the final barrier to protein loss, which explains why podocyte injury is typically associated with marked proteinuria.