Biomaterial Database

Ocular ischemia and the effects of allopurinol on functional recovery in the retina of the arterially perfused cat eye. 1993

N S Peachey, and D J Green, and H Ripps

Department of Ophthalmology and Visual Sciences, University of Illinois, Chicago College of Medicine 60612.

OBJECTIVE This study sought to examine the acute effects of ocular ischemia and reperfusion on retinal function and determine the extent to which recovery during reperfusion is improved by allopurinol (AP), a blocker of xanthine oxidase (XO). The latter is presumed to be a major factor in the formation of free radicals associated with reperfusion of ischemic tissue. METHODS Electroretinographic (ERG) responses were recorded simultaneously from the two isolated, arterially perfused eyes obtained from the same cat. One eye served as the control and received only the standard perfusate; the other eye was infused with AP before and after a 3 hr period of total ischemia. RESULTS After the prolonged period of nonperfusion, recovery of the electroretinographic components was incomplete to varying degrees. Maximum b-wave amplitudes recovered only to 17 +/- 5% (mean +/- SEM) of baseline, whereas the a-wave grew to 60 +/- 10% of its baseline value. For both measures, the recovery of electroretinographic amplitude was significantly greater in AP-treated eyes than in the control eyes. CONCLUSIONS Generation of free radicals by XO contributes to the retinal damage and loss of function that occurs after a period of ischemia and subsequent reperfusion.

UI	MeSH Term	Description	Entries
D007511	Ischemia	A hypoperfusion of the BLOOD through an organ or tissue caused by a PATHOLOGIC CONSTRICTION or obstruction of its BLOOD VESSELS, or an absence of BLOOD CIRCULATION.	Ischemias
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D012160	Retina	The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.	Ora Serrata
D012161	Retinal Artery	Central retinal artery and its branches. It arises from the ophthalmic artery, pierces the optic nerve and runs through its center, enters the eye through the porus opticus and branches to supply the retina.	Central Retinal Artery,Arteries, Central Retinal,Arteries, Retinal,Artery, Central Retinal,Artery, Retinal,Central Retinal Arteries,Retinal Arteries,Retinal Arteries, Central,Retinal Artery, Central
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D003623	Dark Adaptation	Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.	Scotopic Adaptation,Adaptation, Dark,Adaptation, Scotopic
D004596	Electroretinography	Recording of electric potentials in the retina after stimulation by light.	Electroretinographies
D005260	Female		Females
D005609	Free Radicals	Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. Free radicals include reactive oxygen and nitrogen species (RONS). They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.	Free Radical