ultrastructural study of dermal capillaries in diabetes mellitus

ABSTRACT

Dermal micro vessels were examined by electron microscopy in eight diabetic patients and four age matched control subjects. Alteration in capillary pattern was characterized by being enlarged and often with constricted lumen. The endothelial cells showed plenty of pinocytotic vesicles, microfilaments and inclusion bodies. Pericytes were seen separated from endothelial cells by wider spaces. Thus functional alteration of dermal capillaries was suggested to occur with diabetes mellitus. The ultrastructure of the material comprising the capillary basement membrane was similar in both diabetic and control groups. Thus, no correlation could be made between the degree of thickening of capillary basement membrane [CBMT] and diabetes. However, the consistent thickening of the capillary wall was observed in the pattern and amount of collagen fibrils surrounding the capillary wall or intermingled between the basement membrane layers. The findings suggested that dermal capillary changes were indicative of development of early diabetic dermopathy although dermal [CBMT] was not a perfect diagnostic tool for diabetic micro angiopathy