Table of Contents
What makes up the Juxtaglomerular apparatus histology world?
The macula densa are specialized cells in the distal convoluted tubule that are sensitive to sodium. The juxtaglomerular cells and macula densa make up the juxtaglomerular apparatus.
What is the functional unit of the kidney histology world?
The functional unit of the kidney is the nephron. The nephron can be divided into the glomerulus and uriniferous tubule. The capillary tuft of the nephron is referred to as the glomerulus.
What are the straight vessels in the kidney histology world?
They surround the proximal tubule, loop of Henle, and distal tubule. Vasa recta are the “straight vessels” which arise from some of the efferent arterioles.
What cells are sensitive to sodium concentration?
The cells of the macula densa are sensitive to the concentration of sodium chloride in the distal convoluted tubule.
What are the components of juxtaglomerular apparatus?
The juxtaglomerular apparatus, located in the glomerular hilum, consists of a vascular component (afferent and efferent arterioles and extraglomerular mesangium) and a tubular component (macula densa).
What is juxta glomerular apparatus?
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 type of tissue composes the kidney tubules?
What type of tissue composes the kidney tubules? The kidney tubules are simple cuboidal epithelium. Epithelium lines body cavities and surfaces. Simple cuboidal epithelium is “simple” because it is one cell thick.
What activates macula densa?
The macula densa, in response to the change in the Na concentration in the distal tubules, signals the juxtaglomerular cells to release renin. Renin is stored in granules and the secretion is stimulated by the β-adrenergic response and cAMP augmentation.
What triggers macula densa cells?
Macula densa cells can sense variations in tubular fluid composition, including salt content and metabolites such as succinate. Salt is sensed via the NKCC2 and NHE2, whereas tubular succinate triggers the metabolic receptor GPR91 at the luminal plasma membrane.
What are the 3 components of the juxtaglomerular?
The main components of the JGA are the macula densa of the thick ascending limb, the renin-producing granular cells of the afferent arteriole, and the extraglomerular mesangial cell (Goormaghtigh cell, lacis cell; Figure 47.3).
Which hormone is secreted by the juxtaglomerular apparatus?
Renin
Renin is a hormone secreted by the juxtaglomerular cells of the kidney; it interacts with a plasma protein substrate to produce a decapeptide prohormone angiotensin I.
What is JG cell?
Juxtaglomerular cells (JG cells), also known as granular cells are cells in the kidney that synthesize, store, and secrete the enzyme renin. They are specialized smooth muscle cells mainly in the walls of the afferent arterioles (and some in the efferent arterioles) that deliver blood to the glomerulus.
Are podocytes visceral or parietal?
Parietal podocytes were frequent and predominated around the vascular pole, where they were in continuity with the visceral podocytes. Cells that expressed podocyte proteins were found in 76.6% of the sections of Bowman’s capsule that passed through the vascular pole.
Which epithelium is present in DCT?
The distal convoluted tubule (DCT) is composed of simple cuboidal epithelium. The DCT is located in the cortex and corticomedullary junction.
Where is renin released from macula densa?
Do macula densa cells secrete renin?
Macula densa cells in the distal nephron, according to the classic paradigm, are salt sensors that generate paracrine chemical signals in the juxtaglomerular apparatus to control vital kidney functions, including renal blood flow, glomerular filtration, and renin release.
What is the difference between glomerulus and uriniferous tubule?
The nephron can be divided into the glomerulus and uriniferous tubule. The capillary tuft of the nephron is referred to as the glomerulus. Bowman’s capsule is a double layered cap surrounding the glomerulus. This is the first portion of the uriniferous tubule.
What are the parts of the uriniferous tubule?
1 Department of Biomedicine, Aarhus University, Aarhus, Denmark. [email protected] The uriniferous tubule is divided into the proximal tubule, the intermediate (thin) tubule, the distal tubule and the collecting duct.
What is the epithelium of collecting tubules?
The epithelium of these tubules consist of cuboidal or columnar cells. They empty into collecting ducts that are easy to recognise, because they have large lumens, with pale staining columnar epithelium. Collecting tubules have two main functions: 1. resorb water in response to the hormone vasopressin.
Are collecting tubules part of the nephron?
Collecting tubules are not part of the nephron. The epithelium of these tubules consist of cuboidal or columnar cells. They empty into collecting ducts that are easy to recognise, because they have large lumens, with pale staining columnar epithelium. Collecting tubules have two main functions: