Mycoplasma-enhanced priapism in mice.

Priapism seen occasionally in mice used in various mycoplasmal studies over several years prompted further investigation. Of six strains of young adult male mice inoculated intravenously with Mycoplasma pulmonis, of murine origin, priapism was seen only in CBA mice, penile erections persisting in some for seven to 44 weeks. A few mice given broth medium without mycoplasmas also developed priapism, and mice given five mycoplasmal species, of human origin, developed the condition in a way similar to these controls. However, those given M. pulmonis developed priapism earlier and of longer duration than other mice, suggesting that it was an enhancing factor. The duration of the phenomenon is remarkable and, as yet, has no clear explanation.