Immunolocalization of Heat Shock Proteins in the Retina of Normal Monkey Eyes and Monkey Eyes with Laser-induced Glaucoma

Abstract

Purpose: To examine the expression and localization of heat shock proteins (HSPs) in the retinas of normal and experimentally induced primate glaucoma eyes. These proteins are known to be produced in response to a variety of stresses. Methods: Experimental glaucoma was induced in the right eyes of three adult monkeys by repeated applications of argon laser to the chamber angle. Immunostaining with a panel of antibodies against HSP 90, 70, 60, 47, and 27 was performed on retinal sections prepared from the normal and glaucomatous monkey eyes. Results: The intensity of immunostaining for HSP 90, 60, and 27 was greatly enhanced in the retinas of glaucomatous eyes. Prominent reactivity was observed in the inner retinal layers, especially in the ganglion cell and nerve fiber layers. The staining intensity for HSP 70 was also moderately increased, while immunoreactivity against HSP 47 remained almost unchanged in glaucomatous retinas. Immunostaining against glial fibrillary acidic protein was increased and the immunolabeling pattern appeared to be identical with that of HSP 90 in glaucoma retinas. Conclusions: The level of HSP 90, 70, 60, and 27 in primate retinas was increased in experimentally induced ocular hypertension. The differences in expression pattern suggest that each HSP may have its unique role in responding to damage or injury related to intraocular pressure elevation.