Many authors consider apoptosis as a programmed cell death (PCD). Their opinion is based usually on the dependence of cell death on the protein-opinion and RNA synthesis, on the intranucleosomal fragmentation of DNA and on the expression of genes, which can induce apoptosis. However our analysis of numerous literature data on the apoptotic death (judging by their morphological criteria) of different cell kinds induced by various agents shows: internucleosomal fragmentation of DNA is neither a trigger, nor a reliable proof for apoptotic death; protein- and RNA synthesis, as well as expression of P53 genes is also not a necessary condition for that and is important only in some combinations of the cell type and state and the nature of the damaging agent. Thus, the existence of immanent cell death program requires some more proofs and for present the term PCD may be undoubtedly attributed only to the genetically determined processes intended to remove such cells and organs which become unnecessary for the following development, in short, PCD is a term on the level of organism. We propose that character and sequence of destructive processes at apoptotic cell death are conditioned by the conformational changes in genome as result of the cellular environment changes caused by the action of damaging agents on the cellular membranes.
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