Mouse Abdominal Cavity Research Articles

Experimental salmonellosis. 8. Postinfective immunity and its significance for conferring cellular immunity.

In the process of live-vaccine immunization of Salmonella enteritidis infection in mice, the relation between the number of bacteria in the organs of mice and their protecting effect was studied. Treatment with antibiotics was used to control the number of immunizing bacteria in the tissues. Mice, which were infected with 10(-5) mg (1,000 mouse MLD) of virulent S. enteritidis and treated with kanamycin simultaneously, acquired high antilethal resistance against infection with the same organisms. However, the administration of large amounts of kanamycin, which caused a rapid decrease in bacterial numbers in the organs of infected mice, was incapable of conferring immunity. This indicated the necessity of persistence of live bacteria in the host for the production of immunity. A large number of microorganisms were maintained for 53 weeks in a diffusion chamber inserted into the mouse abdominal cavity. The mice implanted with diffusion chambers containing large numbers of virulent S. enteritidis did not acquire antilethal resistance against infection with the same organisms, although agglutinins against S. enteritidis were observed in these mice. Agglutinin was also found in the fluid contained in diffusion chambers inserted into mice immunized with a killed vaccine of S. enteritidis. This indicated that antibody penetrated the membrane filter of diffusion chambers from outside to inside and vice versa. From these results, it is suggested that contact of live microorganisms with the host cell is necessary for conferring postinfective immunity in salmonellosis.

Mitotic Rate of Spontaneous Mammary Gland Adenocarcinoma in C3H/HeJ Mice

THE mitotic rates and duration of cellular turnover of a great variety of normal organs with cell renewal have been determined, mostly in rodents1,2, and in sporadic instances also in man3. In contrast, information is still limited on the mitotic rates and doubling times of malignant cell populations. Using tritiated thymidine, Baserga et al. determined that Ehrlich ascites tumour cells, lodging in the mouse lung, grew at a constant rate with 100 per cent of the cells dividing every 18–20 h4,5. A similar doubling time of 18 h has been determined with tritiated thymidine by Edwards et al. for Ehrlich ascites tumour cells in the peritoneal cavity of mice6. Oehlert et al., likewise using radioactive thymidine, observed a mean generation time of 17–19.4 h for Ehrlich ascites cells in the mouse abdominal cavity; after intramuscular inoculation of ascites tumour cells, those at the periphery of the resulting tumours showed a mean generation time of 12.6–14.4 h; the mean generation time of the cells in the central tumour regions was 28.2–32.4 h7.

γ-アミノ酪酸の代謝に関する研究

An attempt was made to make a study on an incorporation of GABA with brain when it was administered to a mouse abdominal cavity.1) When 0.5 mg per body gram weight of GABA was administered, the content in the mouse brain was not changed, although the one in the liver was rapidly and yet temporarily increa- sed.2) A one week successive administration, 0.3 mg per body gram weight of daily dosage could not make any change of the content in the brain.3) A study with 14C-GABA revealed a rapid temporary incorporation with the liver and the kidney and, in contrast, considerbly little with the brain.