[Ultrastructural study of the action of cyclosporine on cells of the fungus Aspergillus niger].

Electron microscopy of the ultrastructure of the Aspergillus niger cells exposed to cyclosporine in acute experiments revealed changes in the mycelium morphology, hyphae growth and cell structure in the organism sensitive to cyclosporine. The analysis of the changes showed that the primary target of the cyclosporine action was the cell cytoplasmic membrane. The changes in the matrix of the cytoplasmic membrane, mitochondria and cell wall were likely mediated or secondary after the impairment of the cytoplasmic membrane.