Urinary System - JS - part 1 Flashcards
Which two hormones are produced by the kidney?
- Erythropoietin
- Renin
What is the role of erythropoietin?
Stimulates erythrocyte production
What is the role of renin?
acts on angiotensinogen in the plasma, converting it to angiotensin, which eventually causes vasoconstriction and blood pressure elevation.
What cells release renin?
Juxtaglomerular cells
(T/F) Renin is released in response to a decrease in blood pressure.
True
(T/F) Renin release ultimately impacts on the absorption of sodium and chloride ions.
True
Where is the location of the Juxtaglomerular Apparatus?
Vascular pole of the renal corpuscle
What are the 4 structures of the Juxtaglomerular Apparatus?
- Modified smooth muscle cells of the afferent afteriole
- Modified smooth muscle cells of the efferent arteriole
- Macula densa: of distal tubule
- Extraglomerular mesangial cells
Where is the mesangium?
- the interstitial spaces of the glomerulus between the capillaries.
- The area where phagocytic mesangial cells reside
What are the roles of mesangial cells?
- Help maintain functional integrity of the basal lamina in the filtration barrier by phagocytosing large protein molecules and/or debris
- Also contract to decrease surface area available for filtration.
- Have receptors for angiotensin II and atrial natriuretic factor
What are podocytes?
Modified simple squamous epithelium cells comprising the visceral layer (glomerular epithelium) of renal corpuscle.
What is the appearance of podocytes?
- Stellate
- Unusual in shape
What are podocytes characterized by?
-Several radiating primary processes that give rise to many secondary processes (known as pedicels; foot processes)
Pedicels (secondary processes of podocytes) interdigitate with what?
similar processes from adjacent podocytes.
Between adjacent pedicels are what?
Filtration slits bridged by slit diaphragm (membrane)
What is podocalyxin?
Protein coating on pedicel surface of Bowman’s space that maintains organization and shape of processes.
What are the 3 distinct zones of the Basal Lamina which is a part of the Renal Glomerulus?
- Lamina rara externa
- Lamina densa
- Lamina rare interna
What is area cribrosa?
The perforated tip of the renal papilla, located at the apex of each renal pyramid.
What are the renal columns of Bertin?
Extensions of cortical tissue between adjacent renal pyramids
What make up the medullary rays?
Groups of straight tubules that extend from the base of each renal (medullary) pyramid into the cortex.
The renal lobe consists of?
-A renal pyramid and its closely associated cortical tissue
The renal lobule consists of?
-Consists of a medullary ray (at its center) and the closely assoc cortical tissue surrounding it
All nephrons in a single lobule are drained by?
Same collecting tubules
