The production of smooth endoplasmic reticulum and formation of an abnormal amorphous material by the immature 5-day-old chick hepatocytes in culture under the influence of phenobarbital.
The experiment was performed to see if the 5-day-old chick hepatocytes which normally do not produce smooth endoplasmic reticulum in culture, would do so under the influence of phenobarbital. The results indicated that under the influence of phenobarbital, the 5-day hepatocyte produces a small amount of smooth endoplasmic reticulum. However, a more significant observation is that the 5-day-old hepatocytes in the presence of phenobarbital also produce a large amount of amorphous material which is deposited in circumscribed areas of the cytoplasm. It appears that the amorphous material is initially deposited into the cisternal space of the rough endoplasmic reticulum which dilates and the membrane fragments to release the amorphous substance into the cytoplasm. The 5-day-old chick hepatocytes produce a lot more amorphous material than the 11-day-old cells, which formed so little. If, as suggested by many authors (Banjo & Nemeth, 1976; Ernster & Orrenius, 1965; Orrenius, 1965; Orrenius, Ericsson & Ernster, 1965, some of the enzymes produced as a result of the stimulation of the cells by phenobarbital are inseparably located on the membranes of the endoplasmic reticulum (RER and SER), i.e. the enzymes are only stable when attached to the membrane, it may be that the large amount of enzymes produced by the hypertrophied rough and endoplasmic reticulum (Banjo & Nemeth, 1976) in the 5-day-old hepatocytes in culture under the influence of phenobarbital could not find enough smooth endoplasmic reticulum membrane for attachment in the same 5-day-old cells whose capacity for producing smooth endoplasmic reticulum is very limited. Therefore, this large amount of enzyme and the few membranes are not organized and are therefore liberated, as the amorphous material, into the cytoplasm. The 11-day-old hepatocytes, on the other hand, formed very little amorphous material, and this may be due to its high capacity to make smooth endoplasmic reticulum membranes. It is suggested that the large amount of amorphous material liberated in the 5-day-old cells represents the unorganized enzymes and membranes.
D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000648:ultrastructure; D008099:Liver / Q000648:ultrastructure*; D010634:Phenobarbital / Q000494:pharmacology*
D010634:Phenobarbital