Effects of Arterially Infused Hydroalcoholic <i>Agaricus blazei</i> Extracts on Perfusion Pressure and Oxygen Uptake in the Bivascularly Perfused Rat Liver

Abstract

In a preceding work we have reported experiments showing that an hydroalcoholic exctract of Agaricus blazei is able to exert purinergic effects in the isolated perfused rat liver when it is infused into the portal vein in monovascular perfusion (entry: portal vein; exit: hepatic vein). In the present communication we are presenting and discussing experiments done with the bivascularly perfused rat liver (entry: portal vein + hepatic artery; exit: hepatic vein) in order to verify if the hemodynamic effects also occur in the arterial bed. It was found that the A. blazei extract is also active when infused into the hepatic arterial bed, with differences in both sensitivity and nature of the effects on either perfusion pressure or oxygen consumption. Constriction of the arterial bed required much higher concentrations of the extract than the portal bed. The kinetics of the response was also different, with a biphasic instead of a monophasic response. These results provide a promising starting point for future studies aiming to bring to light more mechanistic details about these and possibly other effects.