Does shortage of Thyroxine cause hypertension or hypotension?

This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.

jdawgydawg

Full Member
5+ Year Member
Joined
Apr 25, 2017
Messages
43
Reaction score
32
There was this question on AAMC Biology Volume 2 Question #71:
Assuming hypothesis B to be correct, which of the following endocrine disorders would cause hypertension that could NOT be rectified by physiologically normal kidneys?
A.an excess of aldosterone
B. an excess of glucagon
C. a shortage of thyroxine
D. a shortage of insulin

The answer is A: Aldosterone is a hormone released by the adrenal glands. physiologically normal kidneys respond to aldosterone by increasing the reabsorption of both sodium and water. This leads to an increase in blood volume and therefore blood pressure.

My question is, I don't understand how AAMC's explanation justifies A as being the correct answer...why can't the kidneys rectify the effects of excess aldosterone??

And,
How does the kidney rectify the effects of B,C, and D option ?
Is excess of glucagon and shortage of insulin going to have similar effects of increasing the blood glucose concentration and thus increase solute concentration of blood causing fluid flow into blood vessels, and so the kidneys are going to respond by increased fluid excretion?
I s the shortage of thyroxine going to cause hypotension instead of hypertension? I read online that hyperthyroidism initially decreases systemic vascular resistance so that stimulates renin release from kidneys and the overall effect is increased BP. So since shortage of thyroxine is like hypothyroidism, is the effect going to be decreased BP?

Members don't see this ad.
 
I think the keywords in this question are physiologically normal kidneys. The role of aldosterone is to increase reabsorption of sodium and water in physiologically normal kidneys in order to increase blood volume and pressure. If a kidney simply decided not to reabsorb sodium and water despite a high level of aldosterone, it would be physiologically abnormal. Hope this offers some clarity.
 
I think the keywords in this question are physiologically normal kidneys. The role of aldosterone is to increase reabsorption of sodium and water in physiologically normal kidneys in order to increase blood volume and pressure. If a kidney simply decided not to reabsorb sodium and water despite a high level of aldosterone, it would be physiologically abnormal. Hope this offers some clarity.

Thank you for that! Also, what about the other options? Physiologically normal kidneys won't respond to those in a way that would cause increase in BP?

I appreciate it so much :)
 
Thank you for that! Also, what about the other options? Physiologically normal kidneys won't respond to those in a way that would cause increase in BP?

I appreciate it so much :)

I make it a point to stop with reasoning after I choose my answer. Perhaps someone else could help with these more, so I don't serve to only confuse myself. Sorry!
 
Members don't see this ad :)
I make it a point to stop with reasoning after I choose my answer. Perhaps someone else could help with these more, so I don't serve to only confuse myself. Sorry!
Actually that's a good advice lol I should stop overthinking it as well:confused:
Thanks so much!!
 
  • Like
Reactions: 1 user
There was this question on AAMC Biology Volume 2 Question #71:
Assuming hypothesis B to be correct, which of the following endocrine disorders would cause hypertension that could NOT be rectified by physiologically normal kidneys?
A.an excess of aldosterone
B. an excess of glucagon
C. a shortage of thyroxine
D. a shortage of insulin

The answer is A: Aldosterone is a hormone released by the adrenal glands. physiologically normal kidneys respond to aldosterone by increasing the reabsorption of both sodium and water. This leads to an increase in blood volume and therefore blood pressure.

My question is, I don't understand how AAMC's explanation justifies A as being the correct answer...why can't the kidneys rectify the effects of excess aldosterone??

And,
How does the kidney rectify the effects of B,C, and D option ?
Is excess of glucagon and shortage of insulin going to have similar effects of increasing the blood glucose concentration and thus increase solute concentration of blood causing fluid flow into blood vessels, and so the kidneys are going to respond by increased fluid excretion?
I s the shortage of thyroxine going to cause hypotension instead of hypertension? I read online that hyperthyroidism initially decreases systemic vascular resistance so that stimulates renin release from kidneys and the overall effect is increased BP. So since shortage of thyroxine is like hypothyroidism, is the effect going to be decreased BP?

The kidneys can't rectify hypertension caused by an excess of aldosterone because the kidneys themselves are acted upon by aldosterone. The hypothesis allows for the kidney to fix hypertension issues not relating to the kidney.
 
  • Like
Reactions: 1 user
Top