• SDN Site Updates

    Hey everyone! The site will be down for approximately 2 hours on Thursday, August 5th for site updates.

  • How To ACE Your Medical School Interview

    In this webinar hosted by SDN with experts from BeMo Academic Consulting, you will learn a simple five-step process to help you translate your interview invitation into an acceptance.

CatsandCradles

SDN Donor
10+ Year Member
5+ Year Member
Oct 11, 2005
1,654
5
Status (Visible)
  1. Other Health Professions Student
Hi guys, I have a kidney question.

I was wondering about this, suppose that there is a tumor causing the parathyroid gland to go crazy and give off tons and tons of PTH.

I know that PTH will increase plasma phosphate, inhibit phosphate reabsorption and phosphate ecxretion.

And I also know that the kidneys will excrete H+ bound to phosphate as H2PO4....And I know that the kidneys also needs to secrete H+ to reform and recover HCO3.

So if there's a ton of PTH causing there to be an abnormally high amount of phosphate to be filtered...

What will this do to the patient's pH? I can't seem to put things together here. I know that HC03 is important when your pH drops below normal. So if the H+ that the kidney is secreting is being taken up more than normal because of all the phosphate...does this mean the person's pH is going to drop through the floor? Or will it not affect pH cause the H will also be excreted from the kidneys as H2P04?

Sorry for all the confusion and
Thanks a million!

C&C
 

Bill_252001

B+
10+ Year Member
Aug 1, 2006
262
0
Chicago
Status (Visible)
  1. Pre-Medical
PTH is associated with calcium regulation, never heard Phosphate being regulated by PTH, although I am not yet a med student.
 

beastmaster

Senior Member
15+ Year Member
Mar 22, 2003
944
2
Status (Visible)
  1. Attending Physician
PTH is associated with calcium regulation, never heard Phosphate being regulated by PTH, although I am not yet a med student.

hahahahahahaaha.... Ok, in exchange for the good laugh I just had, I'll answer the question.

Hyperparathyroidism, by excreting more phosphate and bicarb proximally, would produce a hypokalemic (exchanged for H+) hyperchloremic (exchanged for bicarb) mild metabolic acidosis with a high urine pH. It's called renal tubular acidosis.
 
About the Ads

sistermike

Senior Member
7+ Year Member
15+ Year Member
Apr 6, 2002
341
0
Status (Visible)
PTH is associated with calcium regulation, never heard Phosphate being regulated by PTH, although I am not yet a med student.

You weren't totally off -- I assume you learned this in an undergrad bio class. I, too, am an undergrad student and took my two semesters of A&P and although we learned what the poster said below me... PTH (Parathyroid Hormone) does work to increase blood calcium. Aside from the calcium though, PTH also targets the intestines, kidneys, and of course the bones.
 

Droopy Snoopy

Full Member
10+ Year Member
7+ Year Member
Apr 3, 2006
1,846
21
The Alamo
Status (Visible)
  1. Resident [Any Field]
Hi guys, I have a kidney question.
I was wondering about this, suppose that there is a tumor causing the parathyroid gland to go crazy and give off tons and tons of PTH.
I know that PTH will increase plasma phosphate, inhibit phosphate reabsorption and phosphate ecxretion.
And I also know that the kidneys will excrete H+ bound to phosphate as H2PO4....And I know that the kidneys also needs to secrete H+ to reform and recover HCO3.
So if there's a ton of PTH causing there to be an abnormally high amount of phosphate to be filtered...
What will this do to the patient's pH? I can't seem to put things together here. I know that HC03 is important when your pH drops below normal. So if the H+ that the kidney is secreting is being taken up more than normal because of all the phosphate...does this mean the person's pH is going to drop through the floor? Or will it not affect pH cause the H will also be excreted from the kidneys as H2P04?
Sorry for all the confusion and
Thanks a million!
C&C

By decreasing bicarbonate reabsorption you decrease pH, important because acidification of plasma causes a conformation change in Ca-binding proteins causing them to release Ca (one of the many ways PTH increases plasma Ca). It's not drastic however. You're not going to go around treating alkalotic patients with PTH, or have someone overnight develop massive parathyroid tumors that make pH "drop through the floor"; rather compensatory mechanisms will gradually come into effect.
 

likhary

New Member
10+ Year Member
Aug 14, 2008
1
0
Status (Visible)
  1. Pre-Dental
you right, but What will this do to the patient's pH? I can't seem to put things together here. I know that HC03 is important when your pH drops below normal. So if the H+ that the kidney is secreting is being taken up more than normal because of all the phosphate...does this mean the person's pH is going to drop through the floor? Or will it not affect pH cause the H will also be excreted from the kidneys as H2P04?
 
About the Ads
This thread is more than 12 years old.

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.