Methanol poisoning. A rodent model with structural and functional evidence for retinal involvement.
Methanol ingestion can lead to visual impairment, central nervous system dysfunction, or death. The extent of ocular involvement has been difficult to determine because the toxicity is restricted to humans and nonhuman primates due to species differences in methanol metabolism. A rodent model of methanol toxicity recently developed by us was used to evaluate retinal dysfunction in methanol poisoning. Formic acidemia and visual toxic reactions developed in methanol-intoxicated rats. Electroretinographic analysis indicated a significant early deficit in b-wave amplitude followed by a temporally delayed, lesser reduction in a-wave amplitude. Histologic evaluation of the eyes 60 hours after methanol administration revealed generalized retinal edema and vacuolation in the photoreceptors and retinal pigment epithelium. Ultrastructural examination showed swelling and disruption of the mitochondria in photoreceptor inner segments, optic nerve, and the retinal pigment epithelium. These studies document direct retinal involvement in this nonprimate model of methanol toxicity.
Murray
T G
TG
Department of Ophthalmology, Medical College of Wisconsin, Milwaukee 53226.
Burton
T C
TC
Rajani
C
C
Lewandowski
M F
MF
Burke
J M
JM
Eells
J T
JT
D000818:Animals; D004195:Disease Models, Animal; D004596:Electroretinography / Q000187:drug effects; D005561:Formates / Q000097:blood; D008297:Male; D000432:Methanol / Q000506:poisoning*; D009900:Optic Nerve / Q000187:drug effects; D010786:Photoreceptor Cells / Q000187:drug effects / Q000648:ultrastructure; D010857:Pigment Epithelium of Eye / Q000187:drug effects / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D012160:Retina / Q000187:drug effects / Q000503:physiopathology* / Q000648:ultrastructure; D014786:Vision Disorders / Q000139:chemically induced
D005561:Formates; C030544:formic acid; D000432:Methanol