Dj. Browse et al., AN EVALUATION OF WHETHER DURATION OF PERFUSION ALTERS VASCULAR-RESPONSES IN THE ISOLATED DUAL-PERFUSED RABBIT LIVER, Journal of pharmacological and toxicological methods, 32(2), 1994, pp. 117-122
The isolated dual-perfused rabbit liver has been used to characterize
hepatic arteriaI vascular receptors. These hepatic arterial responses
are reproducible for 2.5 hr. Further studies in relation to the assess
ment of portal venous responses using this model require longer period
s of perfusion. This study was designed to determine if this model is
suitable for the assessment of hepatic arterial and portal venous vasc
ular responses over a 5-hr perfusion period. Hepatic arterial response
s were consistent to all agents during 5 hr of perfusion. Portal venou
s responses to the direct smooth muscle acting agents, sodium nitropru
sside and adenosine, were constant, but the vasoconstrictor responses
to acetylcholine and adenosine 5'-triphosphate (agents that cause an e
ndothelium-independent vasoconstriction and an endothelium-dependent v
asodilatation) were potentiated. Coarse measurements of liver function
were also performed and suggested that the liver remained viable for
the 5 hr of perfusion. These results suggest a decrease in the ability
of the endothelium of the portal venous vasculature to respond to vas
oactive substances as duration of perfusion increases. The possible re
asons for this are discussed.