Cardiophysio Q

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Cardiophysio Q

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5 Posts

renin
Forum Newbie

Topics: 12
Posts: 16

09/16/04 - 11:56 AM

An artery perfusing an autoregulatory organ was clamped and then released after a small interval.

1. Why did the blood flow exceed the pre-clamped level after flow resumed to the tissue?

2. Is this only because of reactive hyperemia ?

3. Is it possible to explain this on the basis of metabolism ?

Any input is appreciated

Renin.

mani
Forum Guru
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Topics: 104
Posts: 1,403

09/16/04 - 04:00 PM

the tissue deprived of blood supply for some time sort of "overcompensates", possibly due to metabolic reasons

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vrach
Forum Junior

Topics: 3
Posts: 79

09/19/04 - 09:26 PM

Due to the lack of blood supply, vasodilatory metabolites accumilate in the tissue and dilate the arterioles in the organ. So once the blood supply is restored there is a hyperperfusion of the tissue.
This is the mechanism of transient hyperemia that occurs after reperfusion to any tissue, not just in autoregulatory organs.

09/24/04 - 12:31 AM

Dear Renin,
The explanation by Vrach is justified by Kaplan Physiology Page 118 Q.11.
I hope it helps.
-Josh

renin
Forum Newbie

Topics: 12
Posts: 16

09/24/04 - 05:17 AM

thanx josh

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