Retinal Electrophysiology Is a Viable Preclinical Biomarker for Drug Penetrance into the Central Nervous System

Abstract

Objective. To examine whether retinal electrophysiology is a useful surrogate marker of drug penetrance into the central nervous system (CNS). Materials and Methods. Brain and retinal electrophysiology were assessed with full-field visually evoked potentials and electroretinograms in conscious and anaesthetised rats following systemic or local administrations of centrally penetrant (muscimol) or nonpenetrant (isoguvacine) compounds. Results. Local injections into the eye/brain bypassed the blood neural barriers and produced changes in retinal/brain responses for both drugs. In conscious animals, systemic administration of muscimol resulted in retinal and brain biopotential changes, whereas systemic delivery of isoguvacine did not. General anaesthesia confounded these outcomes. Conclusions. Retinal electrophysiology, when recorded in conscious animals, shows promise as a viable biomarker of drug penetration into the CNS. In contrast, when conducted under anaesthetised conditions confounds can be induced in both cortical and retinal electrophysiological recordings.

Association between Asymptomatic Unilateral Internal Carotid Artery Stenosis and Electrophysiological Function of the Retina and Optic Nerve

“…It has been proved that ERG responses ensure a good function of whole retina, and the mfERG assesses the macular function. Recently, visual electrophysiological tests were proposed to evaluate preoperative macular function, which is used to predict the outcome of cataract surgery [ 41 ] or as a viable indicator of drug penetration into the central nervous system through the blood-neural barriers [ 42 ]. Our findings would support the notion of using the ERG testing also as a new biomarker to assess retinal blood flow conditions that can be affected by hemodynamically significant ICAS in apparently healthy eyes.…”