Ultrastructural Changes Induced by Terbinafine, a New Antifungal Agent, in Trichophyton mentagrophytes

Abstract

The effect of terbinafine, a new allylamine class of antifungal agent, on the ultrastructure of growing hyphae of Trichophyton mentagrophytes cultures in a liquid medium was investigated by scanning and transmission electron microscopy. Hyphal growth was inhibited at terbinafine concentrations above 0.2 ng/ml and several morphological changes such as bending and swelling of hyphae could be observed by scanning electron microscope. Many electron dense granular structures were found in the space between the cell wall and the cytoplasmic membrane, and also in the cytoplasm. Cultures exposed to higher concentrations of terbinafine showed destroyed or collapsed hyphae. In thin sections, degeneration of the cytoplasmic membrane, nuclear membrane and mitochondrial membrane were visible.