[Ahmed-USMLE]

What does insulin do to potassium and what does potassium do to insulin secretion is a concept that is frequently tested in USMLE Step 1.
Let's summarize here and I'd be happy if you enrich this thread with your valuable posts.

• Insulin causes Potassium to shift into the cells thereby decreasing the extracellular K level. That's why insulin is used in the treatment of hyperkalemia.
• Level of Potassium in the serum also affects insulin secretion from the pancreas. Because the beta cells have an ATP dependent K channel which is when closed leads to retained K inside the beta cell which favors depolarization thereby enhancing Calcium mediated release of secretory granules. Therefore, in hyperkalemia more K will enter the beta cell and insulin secretion will increase and conversely in hypokalemia the K ions are more likely to leave the beta cell and so insulin secretion will decrease.

 

[syedaanaqvi]

thanks..it will help many

 

[DrSeddik]

Thanx for the useful post. I was aware of insulin effect on K but not the reverse.

In DKA (insulin deficiency) K is shifted extracellularly but is also lost in urine, so the patient's intracellular K is much depleted than the serum test.

I also find it very useful for the USMLE and real life to know other causes of K intracellular shift (not necessarily loss), these include:

1- B2 effect: That's why you should check K level after you give multiple doses of bronchodilator to patient in severe asthmatic attack. It's also used in rapid adjunctive treatment of hyperkalemia. B blockers cause hyperkalemia.
2-Alkalosis: so most of the time you see alkalosis you see hypokalemia in association, exceptions include loss of intestinal fluid (diarrhea, villous adenoma) and RTA types 1 and 2. Alkalosis also increases K excretion. Acidosis cause extracellular K shift.
3-A very rare disorder that is really not worth mentioning is hypokalemic periodic paralysis.

 

[syedaanaqvi]

i could not find much of all this in kaplan, sorry but please if u could tell the source then it would be great. thanks

 

[Ahmed-USMLE]

i could not find much of all this in kaplan, sorry but please if u could tell the source then it would be great. thanks

Here's a quote from the Merck Manual
http://www.merck.com/mmpe/sec12/ch156/ch156f.html#sec12-ch156-ch156f-785
Here's an article from SpringerLink
http://www.springerlink.com/content/qq127wxj4cnwq6cd/

 

[DrSeddik]

my source is Davidson's medicine 2006 edition which I think is a very useful tool, not to prepare for the boards, but I would definitely choose to study from it in med school.

The info are mostly in hypokalemia section

 

[shwelhtet]

Thanx for the useful post. I was aware of insulin effect on K but not the reverse.

In DKA (insulin deficiency) K is shifted extracellularly but is also lost in urine, so the patient's intracellular K is much depleted than the serum test.

I also find it very useful for the USMLE and real life to know other causes of K intracellular shift (not necessarily loss), these include:

1- B2 effect: That's why you should check K level after you give multiple doses of bronchodilator to patient in severe asthmatic attack. It's also used in rapid adjunctive treatment of hyperkalemia. B blockers cause hyperkalemia.
2-Alkalosis: so most of the time you see alkalosis you see hypokalemia in association, exceptions include loss of intestinal fluid (diarrhea, villous adenoma) and RTA types 1 and 2. Alkalosis also increases K excretion. Acidosis cause extracellular K shift.
3-A very rare disorder that is really not worth mentioning is hypokalemic periodic paralysis.

And in DKA , shifted K is shifted again into the cell with glucose when we give insulin.So , extracellular K is more depleted. Sorry, if any mistake, as it's my first comment.

 

[boro]

In a person after prolonged starvation, for example in alcoholics, a quick infusion of glucose (which triggers insulin release) may cause hypokalemia.

In individuals with untreated diabetes mellitus, insulin injection can cause hypokalemia.

 

[Jingwei]

Thanks for this wonderful explanation!

Thank you for this explanation. It is really helpful!

 

[wllroque]

thanks for the info bro

 

[Dr. Blitz]

No doubt one of the odd topics in step 1 with a surprisingly easy answer.

 

[alekkrish]

Thanx for the useful post. I was aware of insulin effect on K but not the reverse.

In DKA (insulin deficiency) K is shifted extracellularly but is also lost in urine, so the patient's intracellular K is much depleted than the serum test.

I also find it very useful for the USMLE and real life to know other causes of K intracellular shift (not necessarily loss), these include:

1- B2 effect: That's why you should check K level after you give multiple doses of bronchodilator to patient in severe asthmatic attack. It's also used in rapid adjunctive treatment of hyperkalemia. B blockers cause hyperkalemia.
2-Alkalosis: so most of the time you see alkalosis you see hypokalemia in association, exceptions include loss of intestinal fluid (diarrhea, villous adenoma) and RTA types 1 and 2. Alkalosis also increases K excretion. Acidosis cause extracellular K shift.
3-A very rare disorder that is really not worth mentioning is hypokalemic periodic paralysis.

my small contribution:

beta 2 activation leads to increase in camp and pka activation ---->na k atpase is activated leading to k influx into cells.

 

[alekkrish]

What does insulin do to potassium and what does potassium do to insulin secretion is a concept that is frequently tested in USMLE Step 1.
Let's summarize here and I'd be happy if you enrich this thread with your valuable posts.

• Insulin causes Potassium to shift into the cells thereby decreasing the extracellular K level. That's why insulin is used in the treatment of hyperkalemia.
• Level of Potassium in the serum also affects insulin secretion from the pancreas. Because the beta cells have an ATP dependent K channel which is when closed leads to retained K inside the beta cell which favors depolarization thereby enhancing Calcium mediated release of secretory granules. Therefore, in hyperkalemia more K will enter the beta cell and insulin secretion will increase and conversely in hypokalemia the K ions are more likely to leave the beta cell and so insulin secretion will decrease.

insulin activates na k atpase in some cells causing intercellular k shift..it is used with glucose for hyperkalemia

in DKA the transcellular shift of k is commensurate with shift of water from ICF -->ECF.

 

[Nikk]

thank u

 

[motty]

thank you

thank you so much:happy:)

 

[Zarni]

Diuretics & DM Risk

What does insulin do to potassium and what does potassium do to insulin secretion is a concept that is frequently tested in USMLE Step 1.
Let's summarize here and I'd be happy if you enrich this thread with your valuable posts.

• Insulin causes Potassium to shift into the cells thereby decreasing the extracellular K level. That's why insulin is used in the treatment of hyperkalemia.
• Level of Potassium in the serum also affects insulin secretion from the pancreas. Because the beta cells have an ATP dependent K channel which is when closed leads to retained K inside the beta cell which favors depolarization thereby enhancing Calcium mediated release of secretory granules. Therefore, in hyperkalemia more K will enter the beta cell and insulin secretion will increase and conversely in hypokalemia the K ions are more likely to leave the beta cell and so insulin secretion will decrease.

Sorry to dig up the old threat, while I was studying and this one thing comes up.
Is it the reason they say Diuretics can cause DM?
My thinking process is as below,
--> Diuretics --> K+ loss --> Hypokalemia --> decrease insulin secretion

Kindly guide me.
Thanks