Liver system. IV. More on the liver micro-unit: physics and geometry of its action.

The geometry of liver functional micro-units is described in the light of the immunohistologic features of human hepatocytes stained with a retinol-binding protein antibody. The stained cells were distributed into two ordered sets which provided a provisional representation of the law regulating both the motion and the alternation of the rest-work phases (homopoiesis and homorhesis configurations, respectively) which reflect bistable liver micro-unit equilibrium (auto-isodiasostasis). Oscillations between the HP and HR states generate a relaxation cycle that can be assumed to be shared by all micro-units and to be regulated by feedback mechanisms. A model illustrating the compactness of the liver's global action as a result of the activity of each micro-unit is also proposed.