Hepatocyte Cytodifferentiation And Cell-to-Cell Communication
Coordination of functional diversity with compensatory adaptability requires that the cellular constituents of a tissue or an organ develop intricate communication networks. Such functional needs also dictate that stable alterations in differential gene expression, i.e., cytodifferentiation, be part of the adaptive response. Within the limitations imposed by zonal differences, hepatocytes of the same cord within a lobule function in a coordinated fashion and are amply connected through gap junctions. This synchronization of homologous cells is thought to be effected, in part, by exchange of low molecular weight, soluble signaling substances through the gap junctions. In sexually mature rodents several examples of regionally exclusive expression of proteins within the hepatic lobule are known. In contrast to the literature which describes the importance of intercellular interactions between heterologous cells in stimulating differentiated function of parenchymal hepatocytes, less is known about homologous interactions among parenchymal hepatocytes.