Resumo

CEDENO, Floribel; TONINO, Paola  e  FINOL, Héctor J. Microvasculature ultrastructure in premalignant and malignant lesions of oral mucosa. Acta odontol. venez [online]. 2006, vol.44, n.1, pp.18-21. ISSN 0001-6365.

The process of angiogenesis and vascular remodelling is essential for tumor growth, invasion and metastasis. Tumor blood vessels show structural and functional abnormalities. The aim this work was characterize the ultrastructural alterations of microvasculature in dysplasias and squamous carcinomas of oral mucosa as a model of tumor progression by conventional transmission electron microscopy. Alterations included a variable distribution and number of pinocytotic vesicles and caveolae, as well as proliferation of some organelles in  slight and moderate dysplasias. Likewise, the basement membrane looked reduplicated in both cases and pericytes in some cases was alterations. In oral squamous carcinomas capillary basement membrane was thickened and reduplicated. Endothelial hypertrophy was frequent with edema and also in the pericytes. Endothelial cell cytoplasm infoldings into the lumen were observed in slight and moderate dysplasias and oral squamous carcinoma. The results could suggest an abnormal capillary funtion in relation to metabolic activity and permeability of endothelial cells and pericytes.

Palavras-chave : microvasculature; dysplasia; oral cancer; transmission electron microscopy.