Ultrastructural studies on the respiratory tract of mice inoculated intranasally with L. fermentum.

The ultrastructural modifications of the respiratory tract of mice produced by the intranasally inoculated L. fermentum was evaluated. The genus Lactobacillus has been largely studied from the probiotic effect point of view in different ecological systems. Lactobacilli inoculated in 4 intranasal doses (1 x 10(9) CFU/dose) do not produce fundamental changes at the ultrastructural level in the organs of the respiratory tract studied. The most important finding was the presence of a cellular type with intracellular structures surrounded by membranes exhibiting electron dense paracristalline material parallel arranged.