title: [Effect of ischemia-reperfusion on membrane structure and function in rat retina].
abstract: OBJECTIVE
  To study the effect of ischemia-reperfusion on membrane structure and function in rat retina.
  
  
  METHODS
  Thirty-two SD rats were randomly grouped into 4 groups. Group 1 served as the control group, group 2, 3 and 4 served as reperfusion 3 hours, 30 hours and 5 days respectively. The intraocular pressure (IOP) was raised to occlude retinal and choroidal blood vessels to form retinal ischemia; afterwards the IOP was lowered to normal to allow reperfusion. The animal was sacrificed after reperfusion. The colorimetric determination of phosphorus was used to investigate Na(+)-K(+)-ATPase activity of rat retina; the cellular membrane was labelled by fluorescence probe DPH to detect its fluidity which was measured by means of fluorescence spectrophotometer.
  
  
  RESULTS
  Na(+)-K(+)-ATPase and membrane influidity were damaged at early stage. The longer the ischemia, the more serious was the reperfusion injury.
  
  
  CONCLUSIONS
  The mechanism of the decrease of Na(+)-K(+)-ATPase activity is due to the production of substances involved in peroxidation and excitatory amino acid (EAA) which are produced during reperfusion. They can damage the Na(+)-K(+)-ATPase directly. Lipid peroxidation disrupts membrane integrity and causes decrease of membrane influidity. For these reasons, membrane stability is reduced and Na(+)-K(+)-ATPase protein function is changed.
authors.affiliation: Department of Ophthalmology, Jinan Command General Hospital of PLA, Jinan 250031.
authors.forename: L
authors.initials: L
authors.lastname: Zhou
authors.forename: K
authors.initials: K
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: Fang
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D007511:Ischemia / Q000378:metabolism*; D015227:Lipid Peroxidation; D008560:Membrane Fluidity; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000378:metabolism*; D012160:Retina / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
chemical_list: D000254:Sodium-Potassium-Exchanging ATPase