Electron Microscopic study of the trabecular meshwork in alphachymotrypsin glaucoma.

Abstract

The trabecular meshwork of 5 rhesus monkeys (Macaca mulatta), 4 saimiris and 8 rats was studied by electron microscopy, and the optic nerve heads were examined by light microscopy as well. The eyes were enucleated at various intervals (15 min to 80 days) after injection of 0.5–1.2 C. Hb units of alphachymotrypsin in the posterior chamber. The intraocular pressure was determined by electromanometry or the Schiotz tonometer. Electron microscopy revealed fine fibrillar material (zonular fragments) in the intertrabecular spaces, which had the same appearance as the remnants of the zonular fibers in the region of the ciliary body. These fibrils, which were about 100 A thick and up to 0.5 μm long, showed no regular periodicity. The distribution of these zonular fragments varied in different sectors of the eyes. In some sectors, zonular fragments were so numerous that the entire filtering area of the inner wall of Schlemm's canal was blocked. In rats, distinct pinocytotic processes could be observed within the endothelium of the inner wall, through which a part of the zonular material might be transported into Schlemm's canal and the adjacent outflow channels.