The skin-dwelling microfilariae of Monanema martini in Lemniscomys striatus as potential drug screening model for onchocerciasis: midazolam effect in vitro.

The murid model of Monanema martini in Lemniscomys striatus was used to evaluate its potential as drug screening model in onchocerciasis. It had been described that the histopathology and the reaction to diethylcarbamazine treatment of this model closely resemble human onchocerciasis. To study further similarities the in vitro effect of midazolam was examined. Skin-dwelling microfilariae (mf) of M. martini were taken by skin snips and placed in either plain phosphat buffered saline or midazolam. Concentrations of 50 micrograms/ml midazolam significantly reduced motility within 15 min. The percentage of fully motile mf dropped to 9.2 and 1.4 after 15 and 30 min, respectively. In contrast to this finding fully motile mf were obtained after intraperitoneal injection of 60 mg/kg BW; but the technique used did not allow to evaluate the in vivo effect of midazolam. The similarities with the human disease and the finding that midazolam paralyses mf of M. martini like mf of O. volvulus in vitro indicate the potential of the model for simulating human onchocerciasis.