Design and optimization of self-microemulsifying drug delivery system (SMEDDS) of felodipine for chronotherapeutic application

The objective of this study was to determine the effect of medroxyprogesterone acetate (DMPA) on the development and maintenance of Candida albicans in the vagina of oophorectomized Wistar rats. The animals were divided into negative control groups (NCG), which received injections of sterile saline; positive control groups (PCG), which were given injections of estradiol valerate; and progesterone groups (PG), which were given injections of Depo-Provera®. After one week of hormonal induction, vaginal infection by C. albicans was induced in all the groups and detected by vaginal yeast culture and Papanicolaou smear. In addition, scanning and transmission electron microscopy images were obtained to confirm the vaginal infection by yeast in PG. A difference in progesterone levels in PG was observed between the basal level and after hormonal induction (P<0.0001). In this group, 100% of the rats acquired vaginal infection in the first week, but did not maintain it until the third week. The pharmaceutical brand of DMPA was effective for inducing the metestrus or diestrus phase of the estrous cycle in rats, similar to the use of pure progesterone. In contrast to estrogen treatment, progesterone alone could not support an experimental vaginal infection by C. albicans for any significant period of time.