Nonlysosomal cytoplasmic degradation.

Several types of cytoplasmic and nuclear inclusions represent stages in the process of non-lysosomal cytoplasmic degradation. Nonlysosomal degradation takes place in regions where cytoplasmic components are trapped and not accessible to primary and secondary lysosomes. Such trapping occurs within the lumina of the nuclear envelope and of endoplasmic reticulum in the form of inverted vesicles, within the nucleus, within mitochondria and within cavities formed by the process of topolysis in neutral lipid droplets. The concept of the process of nonlysosomal degradation permits dynamic interpretation of various inclusions as the concept of the process of focal cytoplasmic degration (autophagy) leads to dynamic interpretation of the lysosome.