[Ultrastructure of glioma vessel--morphometric study for proliferative potential of endothelial cell]

Abstract

In this study we quantified the morphological abnormalities of human glioma vasculature in operated sample of low grade astrocytomas and malignant gliomas. Only those vessels with a diameter of less than 10 micron and containing one nucleus at least on axial section present in the marginal area of the tumors devoid of necrosis were subjected to the present study. A total of 58 vessels were analyzed with computer assisted morphometry for ultrastructural evidence of proliferative potentials of endothelial cells. 5 specific features of the endothelial cells and/or the capillaries which were not related to the vascular permeability were assessed: (1) Degree of vascular luminal narrowing (LN: Ratio of luminal area to abluminal area), (2) Thickness of basement membrane (BM), (3) Mean % ratio of the endothelial cells including Weibel-Palade bodies to whole endothelial cells (WPB-1) and the number of Weibel-Palade bodies in an endothelial cell section (WPB-2), (4) Irregularity of nuclear shape (NA: semiquantified grade 0 to 3). (5) Mitochondrial density (MIT). We found that: (1) LN was significantly stronger in malignant glioma capillaries (MGC, 28%) than low grade astrocytoma capillaries (LAC, 39%). (2) BM was significantly thicker in MGC (2.9 microns) than in LAC (1.2 microns), (3) WPB-1 and WPB-2 were significantly higher in MGC (34% and 0.92) than LAC (14% and 0.39). (4) NA was significantly higher in MGC (grade 2.1) than LAC (grade 1.3), (5) MIT was significantly higher in MGC (5.6%) than LAC (4.2%).(ABSTRACT TRUNCATED AT 250 WORDS)