Endothelial Cells Filopodia Participation In The Anastomosis Of CNS Capillaries

Abstract

By combining the classic Golgi method and the electron microscope, we have gained a better understanding of the anastomosis of CNS blood capillaries. The participation of growing capillary leading endothelial cells filopodia in the anastomotic process is described. The two approaching capillaries leading endothelial cells filopodia intermingle and interact forming complex conglomerates with narrow spaces filled with proteinaceous material (possibly basal lamina) secreted by them. The presence of tight junctions among the filopodia corroborates their vascular nature. Their presence also suggests a different endothelial cells origin as will those from the two approaching capillaries. The original narrow spaces coalesce into larger ones leading to the eventual formation of a single one that will interconnect (anastomose) the two capillaries. The newly formed post-anastomotic CNS capillaries are rather small with irregular and narrow lumina that might permit the passage of fluid but not yet of blood cells. Eventually, the new capillaries lumina will enlarge permitting the passage of blood cells.\n\nFunding informationThe M. M-P. Golgi studies were supported by a \"Jacob Javits Neurosciences Investigator Award\". NIH Grant NS-22897. And the L. H. EM studies were supported by the Gilman Fund/Class of 1978 Life Sciences Center. M. M-P. is Emeritus Professor of Pathology and Pediatrics and L. H. is a Consulting Electron Microscopists. Both from the Geisel School of Medicine at Dartmouth. Hanover, NH 03755, USA