Microcirculatory characterization of cerebral angiogenesis in mice using intravital videomicroscopy

The present study investigated microcirculatory characteristics of the cere bral neovasculature induced in mice, using basic fibroblast growth factor ( bFGF) and platelet derived growth factor (PDGF). The nylon-mesh sandwich (c ollagen gel/growth factor in bovine serum albumin embedded in between two n ylon-mesh pieces) was used to induce angiogenesis. After different days of incubation, the observations of neocapillaries were done on the upper surfa ce of the nylon-mesh, using fluorescence video-microscopy. The neocapillary diameter, red cell velocity, and the neocapillary density were evaluated b ased on the video-image. The neocapillaries were visible on the upper surfa ce of the mesh on the 6th day after the incubation, and red cells started t o flow from the day 7. The neocapillary red cell velocity increased with da ys after incubation, but its level was less than that of the pre-existing c apillaries. The neocapillary diameter decreased as the neocapillaries got m atured. The neocapillary density was dependent on the doses of bFGF and PDG F The neocapillary diameter did not alter with the higher concentration as well as with different growth factors. Both bFGF and PDGF showed an increas e in red cell velocity at high concentration.