Thromboxane A2 analogue contracts predominantly the hepatic veins in isolated canine liver.


Journal Article

Thromboxane A2 (TxA2) is a potent vasoconstrictor and has been implicated as a mediator of liver diseases such as ischemic-reperfusion injury. We determined the effects of TxA2 and the well-known hepatic venoconstrictor histamine, on the vascular resistance distribution and liver weight in isolated canine livers perfused with blood via the portal vein. The stable TxA2 (STA2; 20 micrograms, n = 5) and histamine (5 micrograms, n = 6) similarly increased the hepatic total vascular resistance, 2.5- and 2.4-fold, respectively. The increase in the hepatic venous resistance was significantly greater than that of the portal resistance (threefold vs. 1.9-fold for STA2; threefold vs. 1.8-fold for histamine). Predominant hepatic venoconstriction induced by both agents was confirmed in livers perfused in a reverse direction from the hepatic vein to the portal vein, as shown by marked precapillary vasoconstriction. STA2 transiently increased liver weight loss (-3.6 g/100 g liver weight), followed by a gradual weight gain (9.0 g/100 g). Histamine caused a progressive weight gain (9.1 g/100 g). In conclusion, similar to histamine, TxA2 constricts predominantly the hepatic vein in isolated canine livers.

Full Text

Cited Authors

  • Urayama, H; Shibamoto, T; Wang, HG; Koyama, S

Published Date

  • December 1996

Published In

Volume / Issue

  • 52 / 6

Start / End Page

  • 483 - 495

PubMed ID

  • 8979308

Pubmed Central ID

  • 8979308

International Standard Serial Number (ISSN)

  • 0090-6980

Digital Object Identifier (DOI)

  • 10.1016/s0090-6980(96)00124-4


  • eng