Fungal morphology after treatment with itraconazole as a single oral dose in experimental vaginal candidosis in rats.

The therapeutic effect of a single, oral dose of itraconazole was studied in rats inoculated intravaginally with Candida albicans and in which an established vaginal infection was present. We used light microscopy, transmission and scanning electron microscopy to document the structural alterations in the 3 days after treatment. The most important observations include the speed (within 24 hours) with which itraconazole inhibits the further penetration of the fungus into the vaginal squamous epithelium, the ability of the drug to reach and structurally alter intracellularly located fungal elements, and the prolonged drug effect of a single dose leading to complete eradication of the fungus from the vagina within 3 days.

Identification of macrophages in intimal thickening of rat carotid arteries by cytochemical localization of purine nucleoside phosphorylase.

Complete desquamation of the endothelium of the rat carotid artery by balloon catheter stripping resulted within 2 weeks in the formation of a large intimal thickening. After an enzyme cytochemical technique was applied to localize cytosolic purine nucleoside phosphorylase (PNP), light microscopical evaluation indicated that this intimal thickening in normocholesterolemic rats was composed of 5.8% to 11.8% (mean 8.8%) PNP-positive cells. At the electron microscopic level, all these PNP-positive cells were identified as macrophages by the absence of a basement membrane and plasmalemmal vesicles and by the occurrence of specific intracytoplasmic granules. The nearly nonreactive intimal cells were classified as modified smooth muscle cells. Additional evidence of the macrophage nature of the PNP-stained intimal cells was obtained by differential immunogold labeling of these cells with a monoclonal antibody against rat macrophages. Moreover, in hypercholesterolemic rats, only the cells stained for PNP transformed into foam cells (between 8.5% and 11.4% of all nucleated intimal cells; mean 9.6%). This study shows that PNP cytochemistry discriminates macrophages from modified smooth muscle cells in the rat carotid intimal thickening. It further suggests that the intimal thickening in normocholesterolemic rats originates not only from migration and proliferation of smooth muscle cells, but also from a considerable number of leukocyte-derived macrophages. Whether the latter cells are actively involved in the establishment of the intimal thickening as has been suggested in dietary hypercholesterolemia, remains to be verified.