Abstract
Liver has a functional zonation relating metabolism and oxygen gradient is considered a determinant of zone formation. It is important to reproduce the microenvironment in vitro, lack of techniques limited experiments at fixed oxygen concentrations. We designed a cell culture microdevice with an oxygen gradient to reproduce the hepatic microenvironment in vitro. The oxygen gradient during cell culture was monitored using a laser-assisted phosphorescence quenching method. Culture medium was continuously exchanged through microchannels without transient hyper-oxygenation. The measured oxygen gradient corresponded well to the simulated gradient, and antimycin A changed the oxygen gradient profile, indicating that cellular respiration change the gradient by consuming oxygen. RT-PCR analysis of hepatocytes cultured under the oxygen gradient showed that mRNA expression of PEPCK and GK significantly increased in culture areas. These results indicate that the developed microdevice can reproduce the hepatic lobular microenvironment. It could be expected to mimic the oxygen gradient of various organs, and it may be applicable to other pathological models.
