Resumen de Role of nitric oxide in murine cytomegalovirus (MCMV) infection
Cytomega lov iru s (C MV ) is a typical pathogen of an opportunistic infection . In this review article , various roles of nitric ox id e ( 0 ) in murine CMV (MCMV) infections, including acute, persistent and latent infections, are discussed. In the acute phase of MCMV infection , NO pl ays a protective role against MCMV infection . In contrast, NO has been proven to act as a pathogenic factor in a mode l of MCMV pneumon itis. In MCMV persistent infect ion, when MCMV was detected only in the sa livary gland , T cells of mice were modified to produce a massive amount of such cytokines as TNF-a and IFN -y up on ill vi vo stimulation with anti-CD3. These cytokines then induced mRNA for inducibl e NO synthase (iNOS), thus resulting in the production of a large amo unt of NO. A histochemical st ud y demonstrated that NO damaged bronchial epitheli al ce lls, a nd thereby apparent ly inducing pneumonitis. In the case of a latent infection, when viral DNA was detected in the host in spite of the abse nce of any infec ti ous particle, NO increased the amount of persistently-infected MCMV-DNA. As a result, NO was found to act as "a double edged sword" in the CMV-host relationship.
