The Experimental Study Of Proanthocyanidins On Retina After Acute Ocular Hypertension

Objective Acute ocular hypertension is a common eye emergency case,mainly occurrs in acute angle closure glaucoma, Glaucomatocyclitic crisis, ciliary-block glaucoma and after some intraocular surgery ,etc. when acute ocular hypertension attack, retina ischemia and hypoxia. After blood recanalization again later, oxygen free radicals, excitatory amino acid, intracellular calcium-ion overload, inflammatory cytokines and cell adhesion molecules, which will induce ischemia/reperfusion injury. In this study, we acutely increased the intraocular pressure in rats by infusing anterior chamber to establish the model, from the morphology and function to study rats'retina after ocular hypertension ,at the same time, we make use of proanthocyanidins in these rats. So we can offer preliminary experiment basis to find effective mechanism in retina.Methods Adult and healthy SD rats were divided into normal group, modle group and PC high,low-dose group.We used the 41/2 scalp needle to infuse the anterior chamber one hour to approached the model, and the infusion bottle height was 150cm.Rats in the PC high,low-dose group were injected proanthocyanidins suspl in intraperitoneal, according to 100mg/kg.d and 300mg/kg.d, rats in the normal group and the modle group were injected saline in intraperitoneal part aeq. Perfusion 48h later, retinal activity of superoxide dismutase (superoxide dismutase, SOD), content of maleic dialdehyde (MDA), nitric oxide (NO), calcium ion (Ca2+) and aminoglutaminic acid (Glu) were detected by spectrophotometer. At the same time, make the retinal slices of HE staining in 6h, 24h, 48h and 72h, from light microscopy.Immunization group of semi-quantitative detection of retinal Caspase-3 expression was detected by Immune-histochemistry, and the retinal ultrastructure was observed by transmission electron microscope.Results Compared with the normal retina, retinal SOD activity in model group decreased,with MDA,NO, Ca2+ and Glu content increased;Caspase-3 expression levels increased, with RGC karyopyknosis, shape collapsed. And the membrane is not complete, the nuclear chromatin marginated with apoptotic body. Compared with model group, retinal SOD in the PC high,low-dose group increased, and MDA,NO,Ca2+ and Glu decreased;Caspase-3 expression got lower, retinal ultrastructure damage lessened.Conclusions We successfully established a rat acute ocular hypertension model and can meet the further experiment needs. For retinal injury, proanthocyanidins can increase SOD activity, decrease MDA,NO, Ca2+ and Glu content, degrade express of Caspase-3 to improve retina ultrastructure and protect the retina.