Glio-vascular architecture in the rabbit retina.

Differences between the rabbit and human retinal circulation, and the use of the rabbit eye in a model of experimental retinal neovascularization, necessitates a complete description of the normal vascular structure in the rabbit and its relationship to adjacent tissue, particularly the glia. The gliovascular relationships in the rabbit were studied by scanning and transmission electron microscopy. Utilizing gas compression of the vitreous to clear the wings of overlying vitreous, the authors were able to make detailed observations of retinal surface by scanning electron microscopy. Glial sheaths surrounding a large number of medium size and smaller vessels were observed. The glial sheaths contained cells which were ultrastructurally similar to Müller cells. No isolated glial tufts were observed in avascular areas. Finally, small, smooth-surfaced cells were found adjacent to many vessels. The exact nature and function of these cells remains unknown.