J E Morgan1, H Uchida, J Caprioli. 1. Cardiff Eye Unit, University Hospital of Wales, Heath Park, Cardiff CF4 4XW, UK.
Abstract
AIMS: To determine whether parasol retinal ganglion cells (magnocellular pathway) are selectively lost in the primate model of glaucoma. METHODS: Ocular hypertension was induced in one eye of six Macaca fascicularis monkeys for 6-14 weeks. The retinal ganglion cells in these eyes were labelled retrogradely with the tracer horseradish peroxidase (HRP) implanted into the optic nerve and subsequently examined in retinal whole mount preparations. The degree of retinal ganglion cell loss was estimated from Nissl stained tissue by comparison with the contralateral untreated control eye. RESULTS: In the three glaucomatous retinas with the best labelling 1282 cells could be classified, of which 182 were parasol cells and 1100 were midget cells. Linear regression analysis did not demonstrate a significant reduction in the proportion of parasol to midget cells with increasing cell loss (regression slope 0.023, 95% CI -0.7 to 0.11). Compared with the control eye the cell soma of the remaining retinal ganglion cells in glaucomatous eyes were reduced in size by 20% for parasol cells (p=0.003) and by 16% for midget cells (p <0.001). CONCLUSION: The results of this study do not support the hypothesis that selective loss of parasol retinal ganglion cells occurs in experimental glaucoma. In addition, the change in cell soma size distributions following ocular hypertension suggests that both parasol and midget retinal ganglion cells undergo shrinkage before cell death.
AIMS: To determine whether parasol retinal ganglion cells (magnocellular pathway) are selectively lost in the primate model of glaucoma. METHODS:Ocular hypertension was induced in one eye of six Macaca fascicularis monkeys for 6-14 weeks. The retinal ganglion cells in these eyes were labelled retrogradely with the tracer horseradish peroxidase (HRP) implanted into the optic nerve and subsequently examined in retinal whole mount preparations. The degree of retinal ganglion cell loss was estimated from Nissl stained tissue by comparison with the contralateral untreated control eye. RESULTS: In the three glaucomatous retinas with the best labelling 1282 cells could be classified, of which 182 were parasol cells and 1100 were midget cells. Linear regression analysis did not demonstrate a significant reduction in the proportion of parasol to midget cells with increasing cell loss (regression slope 0.023, 95% CI -0.7 to 0.11). Compared with the control eye the cell soma of the remaining retinal ganglion cells in glaucomatous eyes were reduced in size by 20% for parasol cells (p=0.003) and by 16% for midget cells (p <0.001). CONCLUSION: The results of this study do not support the hypothesis that selective loss of parasol retinal ganglion cells occurs in experimental glaucoma. In addition, the change in cell soma size distributions following ocular hypertension suggests that both parasol and midget retinal ganglion cells undergo shrinkage before cell death.
Authors: S L Graham; S M Drance; B C Chauhan; N V Swindale; P Hnik; F S Mikelberg; G R Douglas Journal: Invest Ophthalmol Vis Sci Date: 1996-12 Impact factor: 4.799
Authors: Adam Hedberg-Buenz; Mark A Christopher; Carly J Lewis; Kimberly A Fernandes; Laura M Dutca; Kai Wang; Todd E Scheetz; Michael D Abràmoff; Richard T Libby; Mona K Garvin; Michael G Anderson Journal: Exp Eye Res Date: 2015-10-22 Impact factor: 3.467
Authors: Katherine T Janssen; Caitlin E Mac Nair; Joel A Dietz; Cassandra L Schlamp; Robert W Nickells Journal: Invest Ophthalmol Vis Sci Date: 2013-03-11 Impact factor: 4.799