Electroretinogram and visual-evoked potential assessment of retinal and central visual function in a rat ocular hypertension model of glaucoma.

Purpose/aim: The aim of the study was to investigate the long-term functional changes that may occur in the retina and visual cortex in a rat ocular hypertension (OHT) model of glaucoma, used in our lab for treatment studies, using electroretinogram (ERG) and visual-evoked potential (VEP) cortical recordings in order to test the hypothesis that experimental glaucoma has differential retinal and central effects.

Materials And Methods: Experimental glaucoma was induced unilaterally in Dark Agouti rats using hypertonic saline injection into the episcleral veins. After 3, 8, 16 and 26 weeks, ERGs and VEPs were recorded under scotopic conditions using brief full-field white flashes (10 μcd s m(-2) to 10.

Changes in the modulation of retinocollicular transmission through group III mGluRs long after an increase in intraocular pressure in a rat model of glaucoma.

Metabotropic glutamate receptors (mGluRs) have been shown to be involved in the modulation of retinocollicular neurotransmission. In glaucoma, retinal ganglion cells (RGCs) degenerate, which may have an implication on this transmission as the superior colliculus is their major central target in the much-used rodent models of the disease. We have investigated this using an in vitro slice preparation of the superior colliculus by eliciting field excitatory postsynaptic potentials (fEPSPs) through optic tract stimulation in a rat ocular hypertension model of glaucoma.

TRPV1 channels control synaptic plasticity in the developing superior colliculus.

Long-term depression (LTD) in the rodent superior colliculus (SC) is regarded as a model of synaptic refinement because it can be induced during development but not in adults. We investigated the role of transient receptor potential vanilloid type-1 (TRPV1) channels in this type of synaptic plasticity. Experiments were carried out in pigmented mice aged between postnatal day 8 (P8) and 42 (P42) and in adult mice.