[Effects of antibacterial preparations on growth of Mycobacterium tuberculosis in a model of primary tuberculous infection in tissue culture].

Bactericidal activity of isoniazid, rifampicin and pyrazinamide in different regimens was studied on 120 mouse lung explants infected with H37Rv M. Tuberculosis. An increase in isoniazid concentration and duration of the exposure entails enhancement of its bactericidal activity. A direct correlation exists between the concentration and the exposure. Rifampicin is active mainly within first 30 minutes of its contact with the infected tissue without further augmentation of bactericidal activity with increasing concentrations and exposure. Pyrazinamide bactericidal activity is not high. Its enhancement depends rather on increasing concentrations than on duration of the exposure.