1996 Volume 37 Issue 4 Pages 251-261
The effects of lanoconazole (LCZ) on the ultrastructure of hyphae of T. rubrum in a liquid medium. were investigated by ultrahigh-resolution low-voltage scanning electron microscopy (UHR-LVSEM) and transmission electron microscopy. SEM images revealed structural changes of the hyphae depending on the drug concentration: 1) when the minimum inhibitory concentration (MIC, 20ng/ml) of the drug was used, hyphae collapsed; 2) in 0.31-2.5ng/ml, there was curling and multibranching; 3) in 0.02-0.078ng/ml, there was exfoliation of the hyphal cell wall; and 4) phased exfoliation from outside to inside of the cell wall occurred concentration-dependently. The cell wall thickened and in these areas electron dense granules accumulated in accord with concentration. Thus LCZ, even at a low concentration of 1/1000 MIC, affects the ultrastructure of hyphae of T. rubrum especially through changes in the cell wall, and this leads to necrosis by degradation of the cytoplasmic structure.