From owner-metabolic-reg@net.bio.net Wed Jul 17 23:00:00 1996
Path: biosci!IR1CBM.CNRS-MRS.FR!athel
From: athel@IR1CBM.CNRS-MRS.FR (Athel)
Newsgroups: bionet.metabolic-reg
Subject: Liver Query
Date: 18 Jul 1996 02:54:59 -0700
Organization: BIOSCI International Newsgroups for Molecular Biology
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Message-ID: <31EE2659.38B1@ir1cbm.cnrs-mrs.fr>
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This is an attempt to answer Jeremy Cohen's question, "Is it true to 
say the liver obtains the majority of its oxygen requirement from the 
portal rather than the hepatic arterial supply? If this is the case is 
there a reason; it would seem to be illogical."

Surprising, but apparently true.

I'm far from being an expert on this, but I asked a colleague, Maria 
Luz Cardenas, and she directed me to Louis Hue at Louvain 
(hue@horm.ucl.ac.be), who confirmed what the question implies. The 
appropriate text for this is B. D. Ross (Clarendon Press, Oxford, 
1972), which contains useful information around pp. 144-145. Some 
relevant quotations from this book are as follows:

"There are two sources of blood supply to the liver, the portal vein 
(80%) and the hepatic artery (20%)"

and

"The hepatic artery provides only a minor part of the total blood 
which is received by the liver. The remainder, various estimated at 
66-86% (Fisher 1963), is derived from the splanchnic bed, via the 
hepatic portal vein, and is relatively desaturated of oxygen. However, 
an oxygen content of only 3.3 volumes % below that in the arterial 
circuit is observed in the portal venous blood of the dog.  The liver 
therefore receives oxygen in considerable excess of its requirements 
from this source."

Regards,

Athel Cornish-Bowden (athel@ir1cbm.cnrs-mrs.fr)


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