Flashcards in Renal Histo- Herron and Nichols Deck (50):
What are the two general regions of the Kidney ?
Cortex and Medulla surrounded by a fibrous capsule
Where do the blood vessels and nerves enter / ureter leave ?
In the Hilum
Where is the kidney located ?
In the retroperiteneum at the level of T12-L1
What is a renal column ?
( Or Berten Column ) is a medullary extension of the renal cortex in between the renal pyramids. It allows the cortex to be better anchored.
What is a cortical lobule ?
A cortical lobule is part of a renal lobe. It consists of the nephrons grouped around a single medullary ray and draining into a single collecting duct.
What is the main function of the kidney ?
To mantain plasma volume and blood pressure. It also produces hormones.
What does a nephron consist of ?
A renal corpuscle and its tubule. The renal capsule is the same thing as Bowmans capsule.
What are the components of the proximal thick segment ?
The proximal convoluted tubule and the proximal straight tubule
What comes after the proximal straight tubule in the nephron ?
The thin limb of the loop of henley
What is the macula densa ?
It is the demarcation point between the proximal tubule and the distal tubule. It is a feedback structure that can sense the amount of fluid in the tubule.
What are the portions of the thick distal segment ?
Medullary thin ascending limb, cortical thick ascending limb, macula densa, distal convuluted tubule, connecting segment, loop of henle.
Are collecting ducts part of the nephron ?
No they conduct urine from the nephron tubules to the renal papilla.
What are the openings in the renal papilla as it projects into the renal calyce ?
The Duct of Bellini
What are the thin segments of the loop of henlie composed of ?
What does the lumen of the proximal tubule look like ?
The lumen of a proximal tubule has a star shaped lumen and a brush border. The lumen of distal tubule is more rounded and the luminal surface of the cells is sharper.
Which has a larger diameter, proximal or distal tubules ?
Proximal tubules generally have a larger diameter and contain a smaller number of nuclei.
What do the cells look like in the collecting ducts ?
They are smaller and more cuboidal than those of the proximal tubule.
What makes up the parietal layer of the corpusle ?
Epithelium that composes bowmans capsule
What makes up the visceral layer of the corpusle ?
The endothelial podocytes. The urinary space is between the parietal and visceral layers.
What are the phagocytes that are distributed amongst the capillaries of the glomerulous ?
The Mesangial cells. They phagocytose debris and provide structural support. They also secrete IL-1 and PDGF in order to repair the glomerulus.
What composes the cortical labrynths ?
The renal corpuscles, proximal and distal convoluted tubules.
What makes up the medullary rays ?
The medullary rays consist of affregation of straight tubules and collecting ducts. They lie between the cortical labyrinths
What is a renal lobule made of ?
A medullary ray and half of a cortical labyrinth on each side.
What is found in the medulla ?
Only tubules and collecting ducts.
What do renal arteries branch into ?
What do lobar arteries branch into ?
What do interlobar arteries branch into ?
What do arcuate arteries branch into ?
What gives rise to the afferent arteriole ?
Interlobular arteries give rise to the afferent arteriole.
What are the peritubular capillaries ?
The efferent arterioles give rise to a second network of capillaries, the peritubular capillaries.
Which is larger the efferent arteriole or the afferent arteriole ?
The afferent arteriole is smaller than the efferent arteriole.
What is the demarcation point between the lobules of the kidney ?
The interlobular arteries.
What are the spaces between pedicells ?
What are the projections from the podocyte ?
Pedicle projections from the cell
What lines the inside of the glomerular capillary ?
Fenestrated endothelial cells, then the basement cells of the glomerulous
What is the principle component of filtration in the glomerulous?
The basement membrane
What are the three components of the filtration apparatus ?
The fenestrated epithelium, basal lamina, and filtration slits.
Can water move through the endothelium ?
Yes very rapidly because the endothelial cells have aquaporin-1
What type of movement does the fenestrated epithelium restrict ?
The movement of red cells and larger negatively charged proteins
What are the components of the basement membrane ?
Heparin Sulfate, Type 4 collagen, and laminin
What are the components of the juxtaglomerular apparatus ?
The juxtaglomerular apparatus consists of the macula densa and the afferent and efferent arterioles. JG cells are specialized cells in the afferent arteriole involved in renin release.
What are the juxtaglomerular cells made of ?
They are modified smooth muscle cells that surround the afferent and efferent arterioles. They communicate with the macula densa and regulate homeostasis
What cells release Renin ?
What type of epithelium lines the UG tract ?
Transitional epithelium in all areas except the lower urethra. The lover part has a stratified epithelium
What are the three layers of the urinary tract ?
Mucosa, Muscularis, and adventitia or serosa.
What propagates the flow of urine ?
Contractions of the muscularis or inner layer
What lines the lumen of the bladder ?
What is the muscular component of the bladder ?
There is an inner longitudinal layer, middle circle, and outer longitudinal layer.
What are mesangial cells ?
Mesenchymal cells with phagocytic properties and contractile properties equivalent to the pericytes around other capillaries. Cells or Ab can get trapped in the GBM and travel to the mesangial matrix.