Retinale Ischämie bei der intraluminalen Fadenokklusionsmethode

The intraluminal suture methode is an established model to induce a focal cerebral ischemia. Considering the blood supply of the retina, the induction of a retinal ischemia with the intraluminal suture methode (ILSM) is possible. In this experiment we induced a transient retinal ischemia in Sprague-Dawley-rats by occluding the blood supply of the retina with ILSM for 180 minutes. The retinal changes were showed by the recording of the electroretinogram (ERG), using cresyl-violet staining and by immunhistochemical staining of astroglial, microglial, cytokin and apoptotic markers. The ERG showed a suppression of the a- and b-wave with only a recovery of 50% of the b-wave amplitude after 48 hours of reperfusion. Immunhistochemistry revealed that the vascular occlusion induced an expression of GFAP and OX-42 with a maximum of immunoreactivity after 3 days. There was no significant increase of cytokine immunhistochemisty. Histological changes such as neuron lost or edema of the inner retinal layer or apoptotic cells could not be observed. The obtained data suggest that the ILSM leads to a transient retinal ischemia with a lasting impairment of retinal function but no neuronal damage