Quantitative measurements of collateral arterial blood flow in nonarterialized rat liver grafts

The early development of arterial blood flow in the grafted liver after orthotopic liver transplantation in the rat without reconstruction of the hepatic artery was studied. Arterial liver blood flow was measured on day 21 after transplantation with NEN-TRAC microspheres (size 15.5 +/- 0.1 microns) and labelled with 103Ru. The arterial liver blood flow in the grafted liver was 0.778 +/- 0.247 ml/min per gram for transplanted rats after 21 days. One day after transplantation, the blood flow was only 0.006 +/- 0.002 ml/min per gram. The results of this study demonstrate that there was no arterial blood flow on day 1 after transplantation, as expected, but that there was a high arterial blood flow in the transplanted liver by day 21. This was also supported by the angiographic findings. The early development of arterial blood flow via collaterals may account for the excellent results that we and others have attained in orthotopic liver transplantation without rearterialization in the rat.