[Induction of the L forms of M. tuberculosis in vivo guinea pigs]

The cell suspension of M. tuberculosis H37Rv was injected into guinea pigs by nares and intraperitoneal, respectively. It was found that the L forms were induced in lungs of guinea pigs the third week after the infection intranasally and the second week after the infection intraperitoneally. The numbers of the L form colonies induced by two infection passage were the highest the eighth week after the infection. There was a decrease in the numbers of bacilli when the numbers of the L forms isolated from lungs increased strikingly. The presence of the L forms was demonstrated directly by electron microscope. The findings suggest that the L forms are easily induced and may be persist for long time in vivo. There is a certain relationship between the induction of the L forms and bacilli dynamic changes.