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Thread: Cardio q3 N*

  1. #1
    Roxanita is offline Senior Member
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    Cardio q3 N*

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    An asymptomatic 42-year-old man with essential hypertension is started on an angiotensin-converting enzyme inhibitor. Which of the following shows the most likely effect of treatment on circulating levels of aldosterone, renin, and bradykinin?
    Aldosterone../..Renin../..Bradykinin
    A) ↓ ↓ ↓
    B) ↓ ↓ ↑
    C) ↓ ↑ ↑
    D) ↑ ↑ no change
    E) ↑ ↑ ↑
    F) ↑ ↑ ↓

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    Asclepius1 is offline Ultimate Member 537 points
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    Re: Cardio q3 N*

    Quote Originally Posted by Roxanita
    An asymptomatic 42-year-old man with essential hypertension is started on an angiotensin-converting enzyme inhibitor. Which of the following shows the most likely effect of treatment on circulating levels of aldosterone, renin, and bradykinin?
    Aldosterone../..Renin../..Bradykinin
    A) ↓ ↓ ↓
    B) ↓ ↓ ↑
    C) ↓ ↑ ↑
    D) ↑ ↑ no change
    E) ↑ ↑ ↑
    F) ↑ ↑ ↓
    My gues is B. ACE-I increases bradykinin causing cough and decrease the bad stuffs like aldosterone and renin.

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    enlightenedMD2B is offline Junior Member
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    see that is true.. except renin comes before ace.. and always the things that come before will be increased.. ace converts angiotensin I to angiotensin II renin comes before that
    so renin will increase
    bradykinin increase
    and aldosterone decrease
    so i say C
    before you criticize someone .. walk a mile in their shoes... that way you wil be a mile away ... and you will have their shoes. Hidden Content

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    Asclepius1's Avatar
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    Please explain more on why renin increases. Is there some kind of feedback here?

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    Asclepius1's Avatar
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    renin...

    Theory: Renin acts on angiotensinogen from liver converting it to angiotensin I. Then ACE (angiotensin converting enzyme) cuts off two aminoacids from angiotensin I (dekapeptide) and converts it to angiotensin II (oktapeptide). Angiotensin II stimulates the secretion of aldosteron from the adrenal cortex. But, the same ACE that converts AI to AII, in the same time inactivates bradykinin.Conclusion: Inhibition of ACE leads to decreased conversion of angiotensin I (AI) to angiotensin II (AII) so decreasing plasma level of AII. Aldosteron is also decreased because there is no stimulus for its secretion (major stimulus would be AII but there isn't AII because of the inhibition of ACE). But, I have also said that ACE inactivates bradykinin, so when ACE is inhibited, there is an increase in level of bradykinin.So, inactivation of ACE----decreased AII, increased bradikinin, decreased aldosteron
    And, now, what about renin? Why is it increased? To my opinion, renin was secreted due to some stimulus. What are the main stimuli for renin secretion? It is hypovolemia (decreased volume of circulating blood) which causes decreasment of blood pressure. So, because of decreased blood pressure, we must secrete renine in order to increase AII and aldosteron which will then increase blood volume so as blood pressure, by way of reapsorbing water and sodium and stimulating centers for thirst. AII also causes vasoconstriction thus increasing total vascular resistence and the blood pressure. ACE inactivates bradykinin. Bradykinin is in charged for vasodilatation so for decreasing blood pressure. Now, again, why is renin increased? I think it is because the stimulus isn't removed. You see, when blood pressure is decreased, renin is secreted in order to increase blood pressure. But if there is no ACE, then there would be no AII and no aldosteron and too much bradykinin, so blood pressure can't be increased. So, the problem still exists. The stimulus is still present. So, renin is secreted again in order to try to fix the problem, but again there is no ACE, no AII... I think that is the reason for increased renin in case of ACE inhibition. ACE inhibition is one of the ways to treat hypertension. You see that inhibition of ACE decreases AII and aldosterone, but increases bradykinin, so the blood pressure decreases.I am sorry for such a long post.

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    Asclepius1's Avatar
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    Assume answer. I very much appreciate your answer, nver appologize for writing a long post. All it does is help understand the concept even better when somone explains it in such detail. Hope that if time allow you that you will continue answering q'ns that way. You are an ACE in my book.
    Thanks Again

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