Morphological aspects and observations about the permeability of the rat mesentery to the osmium-amine.

In a previous work we felt that many authors were interested in observing the permeability and structure of the mesentery employing many techniques and analysing the material from different points of view. Our collaboration, at that time, was limited to the study of the permeability of the mesentery to the lanthanum nitrate and we came to a final conclusion that the penetration of the heavy salt is impeded by the presence of a basement membrane, localized between the mesothelial and connective tissue layers and that it was continuous to the basal lamina, located between neighbouring mesothelial cells; we could then observe that the lanthanum traveled through the cytoplasm and not in between mesothelial cells. In this paper we analyze the behavior of the mesentery in relation to the osmium-amine and we compare it to the observations made in our previous work. Generally speaking, we were unable to observe any reaction in any of the structures of the mesentery, except for some special cases. In those not very common cases, employing special techniques, we came to the conclusion that the osmium-amine reacts in the periphery (outer surface) of the mesentery and also penetrates, sometimes with no visible reaction, all the way to the elastic layer, where a reaction can be detected.