Kidney - The Renal System Flashcards
1
Q
Kidney
A
- Filters toxins in our blood and putting it in urine to eliminate in your body
- Sit posterior of the abdominal wall T11 and L3 a little protection from lower 2 ribs
- Left kidney sits high than the right bc the liver sits above
- Hilum where all the blood vessels are entering and exiting similar to the lungs. Liver called (porta hepatis) . urine will exit through the hilum
- Renal artery bringing oxygenated blood to the kidney - bloods going to be filtered then will head out to Renel vein and back inferior vena cava
2
Q
View from above
A
- Retroperitoneal organs - not part of peritoneum they’re not wrapped in peritoneal membrane
- Kidneys sits posterior to peritoneal cavity
- Support tissue layers
- inner layer Fibrous Capsule - outer most layer of kidneys - dense connective tissue
- Perirenal fat capsule - kidneys surrounded by fat to provide protection
- Renal fascia - dense irregular connective tissue connecting the kideys to all the surrounding tissues help hold them in place. held in place bc of connections to the peritoneum, to the posterior abdominal wall to other structure
3
Q
Frontal plane of kidney
A
- Renal Cortex - outer most layer
- Renal medulla - inner part
- Renal pyramid in renal medulla - make up the renal medulla
- Renal colums separate renal pyramid
- Calyces - at the point of renal pyramid - collecting area and first droplets of urine are form
- at each point of renal pyramid we have a minor calyx feeds into a larger area
- major calyx are the collecting areas - they will feed into the Renal Pelvis and that will get pushed down into the ureter which heads down towards the bladder
4
Q
Bloodvessels in the Kidney
A
- Renal artery coming in- branching from the abdominal arota
- Segemntal Artery 1 of 5 segmental arteries *
- Interlobar artery* - splitting going btwn the pyramids
- Arcuate Artery - will branch and head out towards that fubrous capsule call those the cortical radiate arteries
- Cortical Radiate Artery - outwards like rays from the sun
5
Q
The Nephron
A
- Most Nephron is located in the cortex
- The structure that filters blood and helps to form and concentrate urine (more structure than cell)
- Have a million in each kidney
- Glomerulus the plasma within the blood and filter and some on will move out to Bowman’s capsule and some of the things filtered out will be reclaimed by the body back into the blood supply other things not filtered out will move into the blood supply into the Convoluted Tuble then end Collecting Duct = urine
6
Q
A
- Cordial radiate artery coming in
- we have afferent glomerular arteriole coming off
- mass of capillaries glomerular capillaries which then feed of to efferent glomerular arteriole
- 20% gets filtered and and 80% moves through
- sugar pull into our blood supplies through the Peritubular capillary to reclaim
- Things that didn’t get filtered that we don’t need will move through the Peritubular capillary and put back into the convoluted tubules to excrete as urine
7
Q
A
- Afferent glomerular arteriole is larger the efferent glomerular arteriole
What’s going to happen to the pressure as a result
- pressure will be higher in the efferent glomerular arteriole bc you need more force to move it through as a result of increase pressure will cause fluid to push out into glomerular capillaries and be filtered
- then enter into area called Bowman’s capsule which is a collecting area before that filtrate will move into the proximal convoluted tubule
- At the goleriuli, fluid is pushed out into Bowman’s capsule called filtrate then it’s pushed out bc of the pressure of differential between afferent and efferent arteriole
8
Q
Golmerular capillary
A
- Surface is covered with cells calle Pedocytes epithelial cells that have all little brances and little foot processes that interdigitate and form all these little filtration slits (smaller collander) betwen them which sit between the foot processes of the podocytes given an even narrower filtration piece to filter
- Basement membrane - a collection of extracellular matrix protein that form a basis for cells to attach to. In the kidney at the glomerulis we have the basement membrane that sits between the fenestrations and filtration slits
- what purpose is that going to serve?
- limits what can pass through
- Fenestrated capillary (larger collander)- large pores that allow molecules to move out not large enough to allow cells to move out. Here cells shouldn’t be pushed out
- Filtrate will be pushed through
- Sinusodial capillaries move cells
9
Q
The Nephron
A
- After the plasma’s filtered out we call it filtrate
- Dostal confoluted tubule
- proximal convoulted tubule - reabsorption channels to work to pull the glucose out of the filtrate so it can move back into the pertiular capillaries. pulling glucose out of the filtrate into our blood supply bc we want to keep it
- filtering out also molecules w/special transporters that pull them from the capillaries that are twisting around and put them into the convoulted tubules to be excreted occurs in proximal & distal convoulted tubule
- Loop of Henle - reabsorption of water and lil sodium
- Then goes up distal convoulted tubules where ions will be reabsorbed and secreted and it ultimately feeds into the collecting duct
- Collecting duct is large tube that is shared betwen multiple nephrons
- once it’s urine we don’t pull it back
10
Q
A
- Proximal convoluted tubule cells
- microvilli will help pull the molecules we want to save from the filtrate
- Of the 20%, 99% ends up being reabsorped betwn water and ions
- ATP, mitochondria
- Nephron loop - Loop of Henley
- Simple Squamous - good for diffusion
- No Channels or transporters that are pulling things out. One type of channel for water called aquaporins. water a lil sodium can move through here
- Distal convoluted tubule cells
- cubodial, mitochondria, helps move things out
- Collecting duct cells
- Cudobial cells
- If we know the structure of cell we know what’s it’s function - interrelated
11
Q
A
- Arculate artery to cortical radiate artery to afferent arteriole and efferent arteriole, our glomeruli, and efferent arteriole, we have our filtration here at Bowman’s capsule that filtrate moves into the proximal convoluted tubule in here lots of different ions and molecules will be reaborded into the peritubular capillaries it’s just a continuation of the efferent arteriole then convoluted tubule moves down into the loop of Henle down here we still have the peritubular capillaries surrounding them, then distal convoulted tubules and then the collecting duct. On the way the capillaries become deoxygentated bc of the tubules are using that oxygen for their mitochondria to make ATP so blood does become deoxygenated then ultimately the blood that remains in the capillaries is going to geed into the cortical radiate veins which then go into the arcuate veins, into the interlobar veins, the segmental veins, and finally the renal veins, and pulling that blood out of the kidney to be recirculated back to the heart to be reoxygenated
- Blood continung in these capillaries in the convoluted tubules will be urine which we will remove from the body
- 85% of nephrons are in the renal cortex
- loops of henley and collecting ducts are located within the renal pyramids
12
Q
Juxtaglomerular Complex
A
- Critial to regulate blood pressure to the body
- Granular cells - smooth muscle cells that line our afferent arteriole some that line our efferent arteriole as well
- sense what pressure is in the system for ex. when your pressure are high and have a lot fluid in system. will increase pressure. When pressure drops it’s going to release a hormone Renin - feedback system that regulates blood pressure
- Macula densa cells within the distal convoluted tubules- not sensing pressure bc we’re inside the convoluted tubule but instead sensing solute (how many molcules dissolve in a fluid) concentrations
*
13
Q
Clinicall Correlate: Polycystic Kidney
A
- Mutations in PkD1 or PKd2 gene
- autosomal dominant - 50% pass to your offspring
- autosomal recessivve version of the gene from both mom and dad (fatal in infancy)
- Causes problems w/ Ca2 influx through epithelial cilia in response to fluid movement
- start to compress some of the nephrons and the tubules that prevent those nephrons from doing their function and being able to filter blood progressibely worse and worse and worse
- Cysts are enlarged tubules that fill with fluid which interfere with the filtration process
- Transplant can cure the disease
14
Q
Kidney Stones
A
- Uric acid accumulating
- Recurrent ifection of kidneys, dehydration
- Painful
- moves down the uriter to pass
- We don’t want them to be bathed in the urine
- Treatment:give medication to relax the ureter and help with the passing
- take ultrasonic sound waves kind of talked about for the gallbladder but more effective in the kidneys
*
15
Q
Ureters
A
- Run retroperitoneally through the abdominal cavity
- not covered with the peritoneum instead outermost layer is an adventitia rather than a serosa
- Contrain 3 layers
- mucosa - inner most layer
- muscularis - middle layer - important - actively moving urine down via peristaltic waves.
- adventitita - circumferential
- What layer are we missing compared to our digestive system?
- submucosa layer
- the malt tends to be intergrated with the mucosa
16
Q
What kind of epithelium would you expect to find in the ureter and bladder?
A
- What kind of epithelium would you expect to find in the ureter and bladder?
- transitional epithelium only in bladder and ureter
- Ureteric orificies - one way valve so urine doesn’t move up the ureters as the bladder expands it will actually compress the ureters which also helps to prevent any urine from travel back
- don’t want reflux back up the ureters to the kidneys and have all our nephrons sitting in urine
- Exit point urethra - trigone at the inferior aspect of the bladder - where bacteria starts to replicate
- Ruggae - folds in bladder and takes up less space when it’s not full
- Top of bladder covered with serosa
- bottom of bladder is an adventitia
- Detrusor - smooth muscle triggered there are sesnory receptors that send that message back to the autonomic nervous system and as a result the autonomic nervous system, the parasympathetic system is going trigger the detrusor to try to create urination
- through the urethral sphincter
- the internal urethal sphincter near the trigone - involuntary
- External urethal sphincter - volitional control over until we relax that muscle - skeletonal muscle we can control
