Louise___xX
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Heyy

I was wondering if anyone knew why/how adrenaline increases blood pressure i need to explain it a bit for my coursework you see, is it just the heart rate increases so more blood is being pumped round the body so the pressure is higher?

Any help would be appreciated!

Thanks
Louise x
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DorianGrayism
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You are right. Adrenaline does increase Blood Pressure by increasing heart rate.



I have placed a more complex explanation below, that may be of some help to you.

For this explanation I shall use alpha = A and Beta = B.

Vasodilation is the increase in the size of blood vessels and Vasoconstriction is the opposite.
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Adrenaline combines with both A1 and B2 receptors. These receptors are found throughout the body on different blood vessels.

However they have different effects. B2 causes vasodilation whereas A1 causes vasoconstriction.

B2 receptors are largely found in the blood vessels in the heart and skeletal muscle.

Therefore, during sympathetic release, Adrenaline causes vasodilation in blood vessels of the heart and skeletal muscle.

So, Adrenaline has two effects on the heart. It increases the heart rate AND it also causes vasodilation of surrounding blood vessels. This enables more blood to be pumped around the body by the heart.


The second part is that Adrenaline effects organs with A1 receptors like the vessels in the Kidney. This causes vasconstriction in these vessels. Therefore, there is more blood going to other part of the body that need it, such as the skeletal muscles.


If there is a term or part you do not understand then just say.
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PkT1991
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(Original post by DorianGrayism)
You are right. Adrenaline does increase Blood Pressure by increasing heart rate.



I have placed a more complex explanation below, that may be of some help to you.

For this explanation I shall use alpha = A and Beta = B.

Vasodilation is the increase in the size of blood vessels and Vasoconstriction is the opposite.
-------
Adrenaline combines with both A1 and B2 receptors. These receptors are found throughout the body on different blood vessels.

However they have different effects. B2 causes vasodilation whereas A1 causes vasoconstriction.

B2 receptors are largely found in the blood vessels in the heart and skeletal muscle.

Therefore, during sympathetic release, Adrenaline causes vasodilation in blood vessels of the heart and skeletal muscle.

So, Adrenaline has two effects on the heart. It increases the heart rate AND it also causes vasodilation of surrounding blood vessels. This enables more blood to be pumped around the body by the heart.


The second part is that Adrenaline effects organs with A1 receptors like the vessels in the Kidney. This causes vasconstriction in these vessels. Therefore, there is more blood going to other part of the body that need it, such as the skeletal muscles.


If there is a term or part you do not understand then just say.



Just to add that the receptors are adrenoreceptors and adrenaline works on the heart's beta 2 receptors causing an Inc in HR and also a dec in time delay to the AVN.
The inc HR is achieved by inc SAN depolarisation therefore thereshold is met quicker generating an a/p faster.

Also from the relationship:

CO = HR x SV

Inc HR due to adrenaline on the SAN will cause CO to also inc because they are both proportionate, and also due to adrenaline's vasocontrictive effects on blood vessel, we know that dec vessel diameter inc resistance and so from another relationship we can see that this will effect bp.

Bp = TPR x CO
(Tpr - total peripheral resistance)
Therefore inc in either parameter - tpr or co will inc bp.

Hoped the equations made things clearer.
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PkT1991
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PS. use the equations in your c.w to explain how bp inc from inc in hr and vasocontriction
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DorianGrayism
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Yeh, he is right...concentrate on the equations and structure some of the info I gave you around that.

That would be a much better way to explain it.

I completely forgot about those. Lol
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Stevetoth
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I am wondering, I was recently told I have Hi BP and I believe it is due to adrenaline. I have always tapped my toes, run up stairs and have always maintained my weight. 155lbs/5'11
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AortaStudyMore
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(Original post by PkT1991)
Just to add that the receptors are adrenoreceptors and adrenaline works on the heart's beta 2 receptors causing an Inc in HR and also a dec in time delay to the AVN.
The inc HR is achieved by inc SAN depolarisation therefore thereshold is met quicker generating an a/p faster.

Also from the relationship:

CO = HR x SV

Inc HR due to adrenaline on the SAN will cause CO to also inc because they are both proportionate, and also due to adrenaline's vasocontrictive effects on blood vessel, we know that dec vessel diameter inc resistance and so from another relationship we can see that this will effect bp.

Bp = TPR x CO
(Tpr - total peripheral resistance)
Therefore inc in either parameter - tpr or co will inc bp.

Hoped the equations made things clearer.
HR and contractility are mainly mediated by beta-1 rather than beta-2
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AortaStudyMore
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(Original post by Stevetoth)
I am wondering, I was recently told I have Hi BP and I believe it is due to adrenaline. I have always tapped my toes, run up stairs and have always maintained my weight. 155lbs/5'11
who told you that? If you had it measured in hospital/GP then you might have had white coat hypertension, I don't know how old you are but I expect you're reasonably young, in which case you probably don't have much to worry about, also most cases of high blood pressure have no known cause, so it's probably not really to do with adrenaline, also the main determinant of high blood pressure isn't adrenaline but infact something called the renin-angiotensin-aldosterone axis. However anxiety/stress can raise blood pressure, and if you're genuinely worried then go to a doctor!
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Franny amy
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my advantage rental van with constant during our waiting my daughters surgery and when we found out that everything was OK and the doctor said she would be fine trailing stop and blood pressure skyhigh right why would that
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Franny amy
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How does adrenaline cause your blood pressure to go up after the adrenaline rush
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