LIVER (slides 137,139,140 and 141)

Now look at slide 139 of rat (or cat) liver, which is similar in appearance to human liver. Without the connective tissue boundaries of the pig, the lobules are not nearly so well defined. In low power, however, search for  central  veins  and  portal  areas as before and note the general impression of radiating cords of cells within each lobule.  At higher magnification look for the same features  as  before.  Perhaps  sinusoids  of Kupffer cells or portal canal structures are clearer in this slide than in your last one.  Also, notice the evidence of stored glycogen particles in the hepatic parenchymal cells.  These cells are often binucleate and have prominent nucleoli.

Since this section has been preserved in methacrylate, the parenchymal cells are  unusually clearly outlined. At  high  magnification,  follow  some  cell  membranes  as  they abut neighboring cells and look for tiny, pin hole sized channels  with  no  further  lining, the bile canaliculi, in which the secreted bile flows to ultimately reach the bile ducts in the portal areas. In what direction is the bile flowing within the "classical"  hepatic lobule as defined here? Learn now bile canaliculi look in electron microscopy.