Paracrystalline inclusions in lysosomes of mouse kidney tubule cells induced by vinblastine and vincristine.

Following the simultaneous administration of vinblastine and vincristine, crystalline and paracrystalline structures were observed in the lysosomes of kidney tubule cells of mice. These structures appeared as hexagonal elements with an average diameter of 22 nm, with filaments about 5,5 nm thick located at each angle of the hexagons. They were formed following the aggregation and fusion of several mitochondria, probably from the mitochondrial cristae. In addition, highly osmiophilic, membrane-bound lysosomes were observed, which in cross-section exhibited regular arrays of straight membrane plates with a periodicity of about 10 nm. The extent to which, or even whether, these are associated with the above-mentioned paracrystalline inclusions could not be clearly established.