Biomedical subjects
Publications and source records attributed to M Chalet.
5'nucleotidase activity of the apical border of the epididymal epithelium appears towards the end of the second week during postnatal development. This activity is in correlation with the activity of testicular hormone. Bilateral castration modifies it and testosterone restores this activity.
The epididymal epithelium of the rat has a 5'nucleotidasic activity, which is located in the basal cells and in the apical border of the principal cells. After bilateral castration, the pattern of this enzymatic activity is modified, but it is restored by a testosterone treatment. Bilateral castration abolished the apical activity of the epithelium, while the basal cells remained active. However different migratory aspects of basal cells seem to show their participation in the secretory function of the epithelium. Testosterone thus appears as a regulator for the basal cells activity and this would explain its role in the epididymal function.
In the wall of rat's capillary blood vessels the adenosine triphosphatase is located on the endothelium, the 5'nucleotidase on the perithelial cells. The perithelial cells activities are strong during the inflammatory state, but at the beginning of the phenomenon the nucleotidasic cells become free into the oedematous tissue by preceding and accompagning the fibroblastic differenciation cells.
Transient acantholytic dermatosis is a self-limited, primary acantholytic disease that occurs predominantly in persons over 50 years old. The primary lesions, discrete papules and papulovesicles, are distributed mainly on the chest, back, and thighs and may be intensely pruritic. The disease lasts less than three months in the majority of patients, but occasionally may go on for two or three years. Four distinct histologic patterns are present in the biopsy specimens, namely, Darier-like in which there is focal acantholysis and dyskeratosis overlying suprabasilar clefts; pemphigus vulgaris-like, in which there are a few acantholytic cells above discrete suprabasal clefts having a mostly intact overlying epidermis; Hailey-Hailey-like, in which there are numerous acantholytic cells overlying suprabasilar clefts; and, finally, spongiotic, in which a few acantholytic cells are present within, or contiguous with, spongiotic foci. Some cases show a predominance of one pattern, but more frequently two or more of these patterns can be found in a single biopsy specimen.
The splenic mouse parenchyma presents 3 reticular cells types revealed by histo-enzymatic technics: the phagocytic cells show a strong phosphatasic acid activity, the endothelial cells possess a phosphatasic alcalin or adenosine-triphosphatasic reaction, the perithelial cells are 5' nucleotidasic. These different cells are distributed by forming specific topographic structures in the splenic tissue. The phosphatasic alcalin reticular cells seem to be, with their distribution, characteristic elements of mouse spleen. Indeed the modifications in tumoral animal interest chiefly this cell category. In this case, the reticular cells form a deep and large membrane between marginal zone and perivascular lymphoid sheath of the white pulp. These different reticular cells probably react for the defense system of the animal.
The peritoneal cells of the splenic capsule have no phosphatasic acid acitivity in the three species studied. However they have an ATPasic acitivity in the Rat and the Rabbit's spleen, and a 5'nucleotidasic activity in the Guinea-Pig. These cells are not phagocytic and probably have different origins according to the species.
The histo-enzymatic comparative study of the reticular cells of some rodents' spleens (Rat, Guinea-Pig, Rabbit), shows many differences between these species. Three cell types can be seen; the phosphatasic type is phagocytic and derives from the M.P.S. system, the 5'nucleotidasic is not a phagocytic cell and probably comes from the vascular perithelium, the ATPasic cell is, perhaps, an endothelial cell. These different cells are not equaly distributed in the splenic parenchyma of all animals but one type can be lacking.
By its destructive effect on the small lymphocyte, cortisone was used to separate the T-lymphocyte from other cells which might be found in the same areas. A reticular cell showing a predominant 5' nucleotidasic activity distinct from that of the phosphatasic acid appeared to be a component of the thymus-dependent areas in the splenic white pulp of Rat. Specific correlations seem to exist between this reticular cell and T-lymphocytes. This histoenzymatic feature involves the reticular cell in the process of maturation of the small lymphocyte.
The effect of cyclophosphamide, one potent immunosupressor drug, was used to differenciate the behaviour of two types of Reticular cells, the phosphatasic acid and the 5'nucleotidasic cells. The first exhibit macrophagic and migratory properties, the second are devoid of these criteria but remain associated with the presence of T-lymphocytes. This suggests its possible role in the nutrition and the differential evolution of T-lymphocytes.
The cells connections occuring in thymus-dependent areas of the splenic white pulp of rat between 5'nucleotidasic reticular cells and small lymphocytes allowed to research this same associated cells in the rat lymph node and the human splenic white pulp and lymph node. The locations of the thymus- dependent areas seem different in man and rat.
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