F. Cajone, G. Ragnotti, A. Bernelli‐Zazzera
Jun 1, 1971
Experimental and molecular pathology
Abstract The reestablishment of blood supply to the liver lobes which have suffered ischemia is followed by an increase in protein synthesis only if ischemia did not last longer than 60 minutes. The increase is accompanied by the recovery of a normal polyribosomal pattern. Treatment of the rats with actinomycin D does not prevent this restoration. In the early phase of the reestablishment of circulation there is a sudden formation of monomers. These monosomes respond well to polyuridylic acid (poly-U) in vitro . The monosome formation can be prevented by treatment of the animal with cycloheximide. Treatment with cycloheximide also prevents the disappearance of the polysomal shoulder during ischemia. The results support the hypothesis that the lowering of the polysomal shoulder and the formation of monosomes are not the effect of ribonuclease action, but the consequence of an interference with recycling of ribosomes on mRNA. The recovery of a normal polysomal pattern after ischemia does not depend on the synthesis of new mRNA.