(15). Experimental animal models have been of significant value in studying the pathogenesis of chlamydial infection, particularly the immunopathological sequelae of untreated asymptomatic infection in females-salpingitis, ectopic pregnancy, and tubal infertility. Nonhuman primate models resemble the human disease most closely (19), but these animals are costly and in restricted supply. Guinea pigs, rabbits, and cats have also been used (11,20,21 on fertility. The mouse pneumonitis biovar of C. trachomatis, MoPn, is genetically and antigenically distinct from human biovars (32) but has the advantage that it is a natural mouse pathogen, particularly of the respiratory tract. To our knowledge, the use of this strain in experimental genital tract chemotherapy has been restricted to two studies involving intrabursal inoculation of mice to induce hydrosalpinx and infertility (5, 26) and a third in which C. trachomatis MoPn was introduced intravaginally to progesterone-treated mice. In the last study, therapy experiments were terminated after 12 days and long-term sequelae were not described (3).We report here, for the first time, the development of an upper genital tract infection in progesterone-treated outbred mice caused by intravaginal inoculation with C. trachomatis MoPn, in which salpingitis, hydrosalpinx formation, and loss of fertility were observed. We have used the model to assess the effects of minocycline, doxycycline, amoxicillin-clavulanic acid, and azithromycin on chlamydial shedding and preservation of fertility.
MATERUILS AND METHODS
Organism