PTH - calcium reabsorption

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Mstoothlady2012

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Schaums says that PTH promotes reabsorption of calcium into the efferent arteriole of the kidney tubule. I thought only filtration takes place in the glomerulus & then efferent arteriole divides into branches of pertiubular capillaries & vasa recta, where reabsorption occurs. Do you think it is just poorly worded? May be it is trying to say that reabsorption occurs in the branches of efferent arteriole (peritubular capilaries) & not efferent arteriole itself. Thank you!

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Schaums says that PTH promotes reabsorption of calcium into the efferent arteriole of the kidney tubule. I thought only filtration takes place in the glomerulus & then efferent arteriole divides into branches of pertiubular capillaries & vasa recta, where reabsorption occurs. Do you think it is just poorly worded? May be it is trying to say that reabsorption occurs in the branches of efferent arteriole (peritubular capilaries) & not efferent arteriole itself. Thank you!

Yeah, I completely agree with you misstoothy! Poorly worded
 
Do you think that they will really test that?
I think kidney is imp and its imp to und all the filtration, reabsorption process going on. Also if they put a question like... PTH increases blood calcium level by promoting the reabsorption of calcium in the kidney. Which of the following is most likely place where calcium reabsorption takes place? What would you put?
 
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I think kidney is imp and its imp to und all the filtration, reabsorption process going on. Also if they put a question like... PTH increases blood calcium level by promoting the reabsorption of calcium in the kidney. Which of the following is most likely place where calcium reabsorption takes place? What would you put?
I don't know where Ca2+ 's reabsorption takes place, but I would put proximal conv tubule. What is the correct answer?
 
I don't know where Ca2+ 's reabsorption takes place, but I would put proximal conv tubule. What is the correct answer?
Well, yea regular calcium reabsorption takes place in proximal tubule. But I did some research & found out that PTH sepcifically acts on the distal tubule reabsorption. So I guess the answer would be distal tubule.
 
Good morning SDN. =) I was gonna answer that, but I guess the answer is already posted concerning PTH affect on Ca+ reabsorption at the distal convoluted tubule.

So reabsorption:
- descending limb - only permeable to water
- ascending limb - always impermable to water
- proximal convoluted tubule - where most absportion occurs-glucouse, amino acid, Na+, K+, HCO3-, Cl- and Ca+ -- via diffusion down their electrochemical gradient or secondary transport
- distal convoluted tubule - Ca+ reabsportion promoted by PTH; and more Cl- and Na+ reabsorption.
- collecting duct- reabsportion/secretion depending on ADH/Vassopressin


please add or correct if there is any error.
 
Good morning SDN. =) I was gonna answer that, but I guess the answer is already posted concerning PTH affect on Ca+ reabsorption at the distal convoluted tubule.

So reabsorption:
- descending limb - only permeable to water
- ascending limb - always impermable to water
- proximal convoluted tubule - where most absportion occurs-glucouse, amino acid, Na+, K+, HCO3-, Cl- and Ca+ -- via diffusion down their electrochemical gradient or secondary transport
- distal convoluted tubule - Ca+ reabsportion promoted by PTH; and more Cl- and Na+ reabsorption.
- collecting duct- reabsportion/secretion depending on ADH/Vassopressin


please add or correct if there is any error.
nice summary
 
Good morning SDN. =) I was gonna answer that, but I guess the answer is already posted concerning PTH affect on Ca+ reabsorption at the distal convoluted tubule.

So reabsorption:
- descending limb - only permeable to water
- ascending limb - always impermable to water
- proximal convoluted tubule - where most absportion occurs-glucouse, amino acid, Na+, K+, HCO3-, Cl- and Ca+ -- via diffusion down their electrochemical gradient or secondary transport
- distal convoluted tubule - Ca+ reabsportion promoted by PTH; and more Cl- and Na+ reabsorption.
- collecting duct- reabsportion/secretion depending on ADH/Vassopressin


please add or correct if there is any error.
vasopressin acts both on distal tubule & collecting tubule - increases water permeability

aldosterone acts both on distal tubule & collecting tubule - increases Na+ reabsorption
 
Nice

vasopressin acts both on distal tubule & collecting tubule - increases water permeability

aldosterone acts both on distal tubule & collecting tubule - increases Na+ and waterreabsorption

didn't know talking about urine could be so fun.
 
Nice



didn't know talking about urine could be so fun.
I thought aldosterone increases permeability to sodium only, water just passively follows Na+ right? That is the major difference between aldosterone & ADH.
 
I thought aldosterone increases permeability to sodium only, water just passively follows Na+ right? That is the major difference between aldosterone & ADH.

Yes.

Aldosterone or the RAS (renin-angiotensin system) is activated when you have low blood pressure because you pissed out so much ions. Low Na+ level --> low blood plasma volume --> decrease end diastole volume--> decrease stroke volume ---> decrease in pressure --> activate RAS (increase renin and angiotensinogen) --> increase aldosterone ---> promote reabsorption of Na+ and water .
 
Yes.

Aldosterone or the RAS (renin-angiotensin system) is activated when you have low blood pressure because you pissed out so much ions. Low Na+ level --> low blood plasma volume --> decrease end diastole volume--> decrease stroke volume ---> decrease in pressure --> activate RAS (increase renin and angiotensinogen) --> increase aldosterone ---> promote reabsorption of Na+ and water .

See that is what I am trying to ask you. If the question asked what is the function of aldosterone? If the answer choices were a) Na+ only b) Na+ & water. I would choose a. What would you pick?
 
See that is what I am trying to ask you. If the question asked what is the function of aldosterone? If the answer choices were a) Na+ only b) Na+ & water. I would choose a. What would you pick?

Oh I didn't notice that was the main point of your post. I'm sorry =). I would definitely choose B. I can see why you choose A though, but you cannot help that aldosterone also cause the reabsorption of water.
 
Oh I didn't notice that was the main point of your post. I'm sorry =). I would definitely choose B. I can see why you choose A though, but you cannot help that aldosterone also cause the reabsorption of water.
hmm ok. I guess I am overanalyzing it. Thanks!
 
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