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.what is body's immediate response to hemorrhage (decrease in arterial pressure).
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- Thread starter silveryhair
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Hypovolemia would lead to a decrease in cardiac output. With the body trying to compensate & keep your BP up, you will have a peripheral vasoconstriction along with an inc in heart rate.
Kidneys would sense the hypovolemia & activate the RAAS.
Kidneys would sense the hypovolemia & activate the RAAS.
to add:
Juxtaglomerular apparatus in kidney would sense low blood pressure and low blood volume and would increase renin. Renin converts angiotensinogen into angiotensin, and angiotensinogen converting enzyme (ACE) made by the liver converts angiotensin I into angiotensin ii. Angiotensin will cause vasoconstriction, and increase Aldosterone secretion in blood. Aldosterone is a mineralcorticoid which will increase sodium reabsorption in kidney and thus water will follow into the blood and restore blood volume.
wow.. surprised i remembered all that.
Juxtaglomerular apparatus in kidney would sense low blood pressure and low blood volume and would increase renin. Renin converts angiotensinogen into angiotensin, and angiotensinogen converting enzyme (ACE) made by the liver converts angiotensin I into angiotensin ii. Angiotensin will cause vasoconstriction, and increase Aldosterone secretion in blood. Aldosterone is a mineralcorticoid which will increase sodium reabsorption in kidney and thus water will follow into the blood and restore blood volume.
wow.. surprised i remembered all that.
ohhh
and also, hypovolemia would lead to low preload of the heart. According to Frank Starling's somethingsomething theory, if there is less preload, the heart rate will have to increase to maintain cardiac output. because Cardiac Output = Heart Rate x Stroke Volume.
hrm.. what is Stroke volume?
and also, hypovolemia would lead to low preload of the heart. According to Frank Starling's somethingsomething theory, if there is less preload, the heart rate will have to increase to maintain cardiac output. because Cardiac Output = Heart Rate x Stroke Volume.
hrm.. what is Stroke volume?
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Stroke volume is vol of blood pumped out w/ each beat.
It is "end-diastolic-vol" minus "end-systolic-vol" (EDV - ESV)
Usually it's about 70 ml (along with a HR of approx 70) giving a CO of 5L/min
While I am not sure where ACE is made, it is released by the LUNGS, which is where Ang I ---> Ang II
It is "end-diastolic-vol" minus "end-systolic-vol" (EDV - ESV)
Usually it's about 70 ml (along with a HR of approx 70) giving a CO of 5L/min
While I am not sure where ACE is made, it is released by the LUNGS, which is where Ang I ---> Ang II
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