A&P Final Lecture 5 Notes Flashcards
What happens to the creatinine production, and renal excretion (grams/ day) and plasma creatine concentraion once the GFR drop
It drops as well,
Due to the disruption in the balance the plasma creatinine concentration must increase
What causes a long term increase in the Plasma creatinine concentration (mg/dl)?
-Due to the disruption in the balance the plasma creatinine concentration must increase, over a couple of weeks
-long term and sustained decrease in GFR causes an increases the amount of creatinine production,therefore, renal excretion (grams/ day) gets back to normal
What causes the life span of the remaining nephons to be cut short ?
-Due to higher concentration of toxic compounds that are filtered
-The workload of the remain nephrons are increased
What happens to the remaining kidney’s physical form and the plasma creatinine concentration when the other kidney have been removed?
the kidney becomes larger
plasma creatinine concentration increase
what should we expect to see in the steady state as the result of some pathology disease of the kidney?
-Doubling plasma creatine
-Cutting GFR in half
-Causing and imbalance relationship in the plasma creatine being created and being filtered
Where is most of NBC transporter found within the renal system and what do they transport ?
Proximal tubules
Sodium, bicarb
How did the bicarb get into the tubular lumen?
filtration
What is the key enzyme that places a role in bring bicarb back into the tubular cell?
Carbonic Anhydrase
What is the amino acid use to create to allow the kidney to procduce their ____________ in the kidney?
What is the name (s) and amount of the product produce?
Glutamine ( non - essential amino acid)
2 bicarb - that goes back into the renal interstitum
2 NH3 ( ammonia ) - that is transfer out by the NBC transporter to be use as a protons
After the glutamine metabolism what is the name of the transporteror exchanger that moves the waste product into the tubular lumen?
Ammonium sodium exchanger
Where are the 3 main places we can metabolize glutamine to produce bicarb and ammonium in the tubule system would be
Proximal Tubules (PT) - most important place
Thick ascending limb of the loop of Helen (TAL)
Distal collecting Tubules (DCT)
What is the primary compound that places a large role in regulating the pH in the urine?
Phosphate
What role does angiotensin II places on the glomerular feedback system?
Angiotensin II places a role in glomerular feedback system that helps regulated our GFR
RAA Axis
1. Renin causes a release of angiotensin I
2. Angiotensin I is converted into angiotensin II by ACE
3. Causing an increase in the amount of aldosterone
4. Release from the adrenal glands
Where witihin the renal circulatory system can angiotensin II effects be seen?
-Afferent arterioles
-Efferent arterioles
-Speeding up some of the process in the proximal tubules
What is the name of the receptor that allows Angio II to bind?
Angiotensin II type 1 receptor
What is the MOA of Ang II binding to the receptor?
speeds up the sodium /potassium ATP ase pump
How do Ang II cause the sodium/ hydrogen exchanger speed increase?
Ang II increases the speed up the sodium /potassium ATPase pump
Lowering the concentration of sodium within the cell
Therefore, the sodium / hydrogen causes the exchanger to increase
What affects does angiotensin II have on the renal system?
increase GFR
conserve volume when need
What is the steps in the negative feed back loop that allows the kidney to increase volume involving angiotensin II due to a low BP?
Low BP
Low GFR
Low Sodium /chloride deliver to the macula Desa
renin release
results Angiotension 2 production
increasing the amount of sodium in the tubule
increasing water
Calcium follows what electrolyte in the paracellular pathway?
Chloride
What are the 2 main pathways that calcium take to reenter the proximal tubules?
transcellular pathways
paracellular pathways
What percentage of calcium in the plasma is being filtered and why?
60% of the calcium that is in the plasma that is actual filtered
Calcium is freely filterable
Complicated factors:
-Calcium has 2 charges
-Hangs out near proteins within the plasma concentration (that has a net negative charge)
- 40 % calcium is hanging around the protein, because protein is to large to be filtered the calcium is never filtered
How is calcium transported out of the proximal tubule and into the Renal insterstitium?
Calcium ATPase
Calcium / Sodium exchanger
What is the molecule that helps control calcium
parathyroid hormone
What is the active and inactive form of calcium?
where is it activated ?
inactive - cholecalciferol
active -1,2,5- cholecalciferol
kidney
What part of the tubules where PTH act on to increase calcium reabsorption
Proximal tubule
where are the other 2 places within the system that calcium can be reabsorbed?
Ascending thick end of the loop of helen
Distial collective tubules
What is the name of the cell that is stimulated to breakdown the bone by PTH and to what 2 compounds
osteoclast,
calcium, and phosphate
What is the name of the cell that is inhibited by PTH to produce bone.
osteoblasts
True or false Thin descending LOH is very permeable to ions
False
True or false: the osmolarity of the environment deep within the kidney is low ?
False, deeper we go the higher the osmolarity (more concentrated the renal interstitium is
20% of the water that was filtered is reabsorbed in what part of the renal tubule
Thin Descending LOH
True or false: anything that increases the velocity of fluid flow through the system, increases the urine output
True
How would increased blood velocity affect the water reabsorption in the AVD (ascending vesta recta) and how will that affect our urine output ?
If the velocity too fast, we cannot absorb the salt from the blood there decreasing water absorption
increasing urine output/ making it more dilute
True or false. The water permeability in the ascending loop of helen is permeability to water.
false
Where is the sodium chloride reabsorption pump located in the renal tubule
Thick Asending LOH
What is unique about the sodium chloride reabsorption pump in the direction and time it is pumping.
Pumps in the same direction at the same time moving ions out the tubule
the process of the Thick Ascending LOH ion reabsorption is dependent on what?
Leaky K+ channels
What are the ions reabsorbed at the Thick ascending LOH
Na+, K+, 2Cl-, CA++, Mg+
What is secreted at the Thick ascending LOH
protons, H+
What important benefits does the ions that are reabsorbed at the Thick ascending LOH have on the insterstitium?
Active reabsorption that takes place at the thick ascending LOH becomes important on renal interstitial osmotic gradient
Making it more concentrated and easier to hang on to the fluids ( water conservation)
True or False, Potassium channels can be found on the tubule lumen side of the tutelar cell.
true
What happens to the tubular lumen potassium is able to reenter back in?
portion of potassium goes back out into the tubular lumen, changing the charge of the tubular lumen more positive (8mV)
What effect does potassium has reentering the tubular lumen in the Ascending thick LOH?
-increase the charge of the tubular lumen to +8mV
-Drives reabsorption of the other positively charge ions
How does Mg++, Ca++, and Na+ reenter the renal interstitial fluid from the Ascending thick LOH?
What role does potassium play?
Na+, Mg++, Ca++ moves paracellular between the tight junctions (impermeable to water)
Potassium drives the reabsorption of the other positively charge ions by going back out to the Tubular lumen and increasing to +8mV
What is the most potent drug that affects the thick ascending LOH?
Furosemide
(loop Diurectic)
What is the MOA of furosemide at the Thick ascending LOH?
Stops reabsorption of ions (Na/K/Cl), will keep more water in tubule, increases urine output
end up diluting concentration of renal interstitium
What is the Osmolarity in the proximal tubules?
What happens to the osmolarity has you descend down the proximal tubules?
300 mOms
it increases
What is the diluting segment in the renal tubule ?
Where is it located within the renal tubules?
Diluting segment creates imbalance between osmolarity of tubular fluid compared to intersitium/environment over shoting it to 100mOms
Primarily though Na and Cl pumping in this segment (DCT)
Because reabsorbing salt but not much water
Located:distal convoluted tubules
Which transporter or exchanger does most of the work regarding pumping calcium back into the the interstitial fluid ?
In which portion of the renal tubule the transporter or exchanger can be found?
Na/Ca exchanger
Disital Convoluted Tubules (DCT)
What drug or class of drugs that effects the Na/Cl pump in the distal tubule ?
What is the MOA?
Thiazide Diuretic,
-Inhibits sodium and chloride reabsorption at distal tubule
-Would reduce amount of dilution with tubular fluid
How do PTH regulate the calcium in the distal tubule?
By stimulating calcium reabsorption
-More channels means more calcium reabsorbed from tubular fluid
-Less channels means less calcium reabsorbed and more calcium in the urine
-If want to get rid of calcium, it is filitered and not reabsorb i
-If want to hang on to calcium, it is filitered and reabsorb
How do thiazide diuretics affect the Na/ Ca exchanger
Results in losing salt and water, increasing urine output
Calcium reabsorption increases( due to the low Na gradient inside the cell —> the Na/ca exchanger increase
Spinning NCE faster results in more calcium being reabsorbed ( causing the PTH reabsorbing more Ca+)
Increase in PTH and decrease in Calcium causes what disease to develope
osteoporosis
What are the 2 cell types that are found at the end of the distal tubule ?
principal cells
intercalated cells
What is the job of the principle cells
control potassium levels in the body
What ion channels can be found on the principle cell membrane ?
What side of the tubular cell membrane?
** Apical side ** - Tubular side of principle cell
potassium channels
sodium channels
** Basolateral** - interstital side of principle cell
Cloride
What is the driving force of the potassium and sodium channel in the distal tubules?
The flow of potassium and sodium channels
potassium and sodium is pump in through the Na/K ATPase on the basolateral side of the cell and leaves out through the apical side of cell through individual channels
What would happen if the function of the Na/K ATPase pump was increase?
How would that effect the renal interstital space?
reabsorb more sodium
excrete more potassium
increase the Na gradient concentration
What hormone affects the Na/ K ATPase pump and how do it affect sodium and potassium?
Aldosterone helps us conserve sodium and get rid of potassium
Which hormone determines how many sodium channels we have on the apical side of prinicple cell?
Aldosterone
What is an example of a mineralocorticoid derivative
Aldosterone
Where in the adrenal gland is aldosterone produce?
zona glomerulosa
(The outer portion of the adrenal gland called the)
What are the names of the 2 inner layers within the adrenal gland ?
what is/ are the compond(s) produce?
What is the name of the medial layer of the adrenal gland?
What is /are the name(s) of the compond(s) produce?
**Zona fasciculata
Zona retciularis **
Cortisol
androgens
**medulla **
catecholamines
(NE, EPI, DOP)
True or false, A cholesterol derivative that looks similar to aldosterone may cause the body to increase BP and decrease potassium levels.
true
How do the kidney destroy any cortisol that may enter the principal cell?
by using the enyzme ,(11beta -HSD)
11 beta - hydroxysteroid dehydrogenase that specifically destroy cortisol like compounds but do not act on aldosterone
True or false, The 11 beta - hydroxysteroid dehydrogenase enzyme is able to completely destroy cortisol even if we are taking medication
False
Which hormone is released in response to an increase in the plasma potassium concentration?
What is the MOA?
-Aldosterone
-increases potassium secretion by stimulating the Na/ K ATPase pump at the distal tubules in the prinicple cells
( early part of cortical collecting duct)
What events within the renal tubules can effect the mechanics of fixing an elevated potassium level?
anything that blocks sodium reabsorption earlier in the tubular system
(proximal tubules
ascending thin and thick LOH)
What will happen if we have more sodium in the renal tubules that reaches the principle cells in the distal collecting duct ( the MOA of most of the diuretic)
How will that effect the Na and K concentration?
-large amount of sodium leaking through the sodium channels that we have
-increase large amount of sodium going out of the renal tubules and in to the renal interstitial fluid
-Therefore large amount of potassium will leave out and into the renal tubular lumen ( potassium wasting)
What is the MOA for aldosterone - sensitive (antagonist) drug(s)?
What is an example of one
Spironolactone
Eplerenenone
blocks the hormone receptor of aldosterone therefore decrease the usage of the Na/K ATPase pump
What are the 2nd generation potassium sparing diuretics
What is the MOA in the principle cells in the distal tubule ?
Amiloride
Triamterne
blocks the sodium channels in the principle cell decreasing the amount of sodium reabsorbed
What is the job of the intercalated cells and where are they located?
The cells deal with acid/ base balance by secreting bicarb - secreted
Type B cells
protons ( H+/ NH4+) - selected
Type A cells (more active )
in the later part of the distal tubules early part of the collective ducts
What area in the renal tubule that is sensitive to ADH?
later part of the distal tubules early part of the collective ducts
ADH have receptor(s) on what type of cell(s)
principle cells
intercalated cell
How do ADH impact the renal system?
water permeability
urea reabsorption
What are the pumps that are found in the intercalated cell that regulates Hydrogen?
Hydrogen - potassium ATPase pump
Hydrogen ATPase Pump
What is another abbreviation for ADH?
AVP
What is the name of the receptor on the principle or intercalated cell that the ADH binds to?
V2 - regulator receptor that control water permeability
What is the process to allow water reabsorption when AVP binds to V2?
-AVP binding to V2 causes
-Gs (subunit to be release)
-releasing AC
-causing ATP —> cAMP
-increasing the activity of protein kinase A (PKA)
-causing protein phosphorylation on the collection of premade aquaporins -2 (located in the tubular side of the cell to allow water to be reabsorbed
What happens to the aquaporins -2 when ADH decreases?
they move back to their storage pools
Which hormone is sensitive in the cortical and medullary collecting tubules
AVP
What area in the renal tubules concentrates the remaining filtrate before exiting the kidney?
collecting ducts: cortical & medullary by the H+ ATPase pump
What area in the renal tubular system will be the final determinant of the urinary osmolarity?
collecting ducts: cortical & medullary
Which hormone or compond is the only compound or hormone that can change water reabsorb?
AVP
high volume output witin the renal tubules = AVP levels ________
low volume output within the renal tubules = AVP levels _________
low
high
What part or region of the brain regulates the amount of ADH release to the kidneys?
what is the MOA?
by the osmorecepters located in the hypothalamus
it looks at the blood osmolarity and talks to the posterior lobe in the pituitary gland to increase or decrease the amount of ADH being release
How do the osomoreceptor determine when to increase release of ADH?
if the environment surrounding the osomoreceptor is very salty then the water will leave the cell causing it to shrink little bit until the internal osmolarity matches the environment
How do the osomoreceptor determine to reduce release of ADH?
if the environment surrounding the osomoreceptor is diluted then the water will move in the cell causing it to enlarge little bit until the internal osmolarity matches the environment
