Faculty Collaboration Database

Electroretinogram of the Cone-Dominant Thirteen-Lined Ground Squirrel during Euthermia and Hibernation in Comparison with the Rod-Dominant Brown Norway Rat. Invest Ophthalmol Vis Sci 2020 Jun 03;61(6):6

Date

06/04/2020

Pubmed ID

32492111

Pubmed Central ID

PMC7415905

DOI

10.1167/iovs.61.6.6

Scopus ID

2-s2.0-85085963234 (requires institutional sign-in at Scopus site)   8 Citations

Abstract

PURPOSE: The majority of small animal species used in research are nocturnal, with retinae that are anatomically and functionally dissimilar from humans, complicating their use as disease models. Herein we characterize the retinal structure and electrophysiological function of the diurnal, cone-dominant 13-lined ground squirrel (13-LGS) retina during euthermia and in hibernation.

METHODS: Full-field electroretinography (ERG) was performed in 13-LGS and Brown Norway (BN) rat models to establish baseline values for retinal function in each species, including following intravitreal injection of pharmacologic agents to selectively block the contributions of ON- and OFF-bipolar cells. The effect of hibernation-associated retinal remodeling on electrophysiological function was assessed in 13-LGS during torpor and emergence, with correlative histology performed using transmission electron microscopy.

RESULTS: Under light-adapted conditions, the a-, b-, and d-wave amplitude of the 13-LGS was significantly greater than that of the BN rat. Retinal function was absent in the 13-LGS during hibernation and correlated to widespread disruption of photoreceptor and RPE structure. Remarkably, both retinal function and structure recovered rapidly on emergence from hibernation, with ERG responses reaching normal amplitude within 6 hours.

CONCLUSIONS: ERG responses for both BN rats and 13-LGS reflect the relative proportions of cone photoreceptors present within the retinae, indicating that the cone-dominant 13-LGS may be a potentially useful model for studying human central retinal function and disease. That retinal remodeling and restoration of electrophysiological function occurs rapidly on emergence from hibernation implies the 13-LGS may also be a useful tool for studying aspects of retinal physiology and recovery from injury.

Author List

Zhang H, Sajdak BS, Merriman DK, McCall MA, Carroll J, Lipinski DM

Authors

Joseph J. Carroll PhD Director, Professor in the Ophthalmology and Visual Sciences department at Medical College of Wisconsin
Daniel M. Lipinski PhD Associate Professor in the Ophthalmology and Visual Sciences department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Electroretinography
Excitatory Amino Acid Agonists
Female
Hibernation
Intravitreal Injections
Male
Rats
Rats, Inbred BN
Receptors, Kainic Acid
Receptors, Metabotropic Glutamate
Retina
Retinal Bipolar Cells
Retinal Cone Photoreceptor Cells
Retinal Rod Photoreceptor Cells
Sciuridae
Torpor