1977 Volume 54 Issue 1 Pages 25-59
The several structures in the liver were studied by comparing the differences between ammocoetes (larva form) and adult lamprey (adult form).
Both of ammocoetes and adult lamprey showed double basement laminas within the space of Disse. One beneath the endothelial cell was indistinct and discontinuous. The other, which surrounded the hepatocytic surface facing the space of Disse, was distinct and continuous.
Fat storing cells in the ammocoetes liver contained usually none or only one lipid droplet within their cytoplasm. In the adult lamprey, the number of both fat storing cells and their containing lipid droplets was makedly increased, especially the number of the latter reached usually to ten in maximum.
Bile canaliculi disappeared in the adult lamprey. No junctional complexes on the side of the bile canaliculi were also observed in the adult lamprey.
Gap junctions between adjacent hepatocytes increased in the adult lamprey, while they were rarely observed in the ammocoetes hepatocytes. Lysosomes appeared to converge around the bile canali culi and in the vicinity of Golgi complexes in the ammocoetes hepatocytes. In the adult lamprey, the lysosomes could be merely observed in the vicinity of Golgi complexes. The lysosomes showed a decrease and their amorphous contents were frequently mottled with electron dense granules.
In the cytochemical studies, some of the lysosomes in the ammocoetes hepatocytes showed positive reactions for both of acid phosphatase and peroxidase but no microbodies showing reaction for peroxidase were demonstrated. Lipo somes including giant liposomes consisted of dilated ER filled with electron dense amorphous materials in the adult lamprey hepatocytes.
Many lipid droplets similar to the contents of giant liposomes were observed in the hepatocytes of the late adult lamprey, while neither lipid droplets nor liposomes were observed in the hepatocytes of the ammocoetes liver.