INTRAHEPATIC BLOOD-FLOW DISTRIBUTION IN THE PERFUSED-RAT-LIVER - EFFECT OF HEPATIC-ARTERY PERFUSION

Citation
Fj. Burczynski et al., INTRAHEPATIC BLOOD-FLOW DISTRIBUTION IN THE PERFUSED-RAT-LIVER - EFFECT OF HEPATIC-ARTERY PERFUSION, American journal of physiology: Gastrointestinal and liver physiology, 34(4), 1996, pp. 561-567
Citations number
32
Categorie Soggetti
Physiology
ISSN journal
01931857
Volume
34
Issue
4
Year of publication
1996
Pages
561 - 567
Database
ISI
SICI code
0193-1857(1996)34:4<561:IBDITP>2.0.ZU;2-Q
Abstract
Variations in blood flow to different sinusoids within the liver can p revent uniform uptake of solutes from plasma and contribute to cellula r ischemia in low-flow states. However, the degree of variability and the role of hepatic artery perfusion in maintaining uniform flow are p oorly defined. We used an indicator dilution technique to compare the distribution of sinusoidal transit times in isolated rat livers perfus ed through the portal vein alone with livers perfused using both porta l vein and hepatic artery. Physiological flow rates were used in each case (1.2 +/- 0.3 ml . min(-1). g liver(-1)), but the second group rec eived 32% of flow through the hepatic artery. Intralobular flow hetero geneity was further assessed by gamma counting of small (similar to 10 0 mg) pieces of the liver after bolus injection of similar to 5 mCi of a highly extracted compound ([I-125]triiodothyronine) into the portal vein. Hepatic artery perfusion had no significant effect on mean sinu soidal transit time or intrahepatic distribution volume for Cr-51-labe led red blood cells or I-125-albumin. Analysis of the outflow profiles indicated that hepatic artery perfusion did not affect transit time d ispersion. However, heterogeneity of flow to individual portions of th e liver, measured as the coefficient of variation, increased from 19 t o 30%. These results indicate relatively uniform perfusion of the sinu soids in the portally perfused rat liver and that additional perfusion of the hepatic artery does not further improve hemodynamics. These re sults have significance for the design and interpretation of transport studies with the use of the perfused rat liver model.