Article révisé par les pairs
Résumé : Diabetes mellitus, induced in the rat by alloxan (40 mg/kg b.w.) resulted in permanent hyperglycemia (mean glycemia: 403.0 mg/100 ml). The animals were left untreated for more than 16 mth. The mesangial cells of the renal glomeruli were studied by serial biopsies performed each mth under light anesthesia in the diabetic animals and in normal controls of the same age. Large dense bodies appeared in the cytoplasm after 3 mth in the diabetics and after 10 mth in the controls. With time, a larger number of mesangial cells contained these dense bodies. At the end stage they seem to be mainly lipidic substances. When NO3Ag is given in the drinking water the dense bodies accumulate particles of silver, suggesting that they contain fragments of the basement membrane. While the acid phosphatase reaction was negative in biopsy specimens from diabetic animals, it remains possible that the large dense bodies belong to the lysosomal system. This point, as well as the pathologic significance of the dense bodies is under investigation.