Heat shock protein 70 expression increased in rabbit müller cells in the ischemia-reperfusion model

Heat shock protein 70 (HSP70) expression in the rabbit retina was evaluated in the ischemia-reperfusion model. Ischemia was induced by increasing the pressure in the anterior chamber, and the retinas were collected 1 or 12 h after reperfusion. HSP70 expression was examined by Western blot, confocal laser scanning microscopy and immunoelectron microscopy. Western blot showed that HSP70 was significantly increased in the retina 12 h after reperfusion, compared with normal control or 1 h after reperfusion. Confocal microscopy demonstrated that HSP70 was constitutive in Müller cells and that its expression was increased 12 h after reperfusion. Electron microscopy showed that glycogen-like granules were significantly decreased with prominent endoplasmic reticulum 1 h after reperfusion. Twelve hours after reperfusion, however, the density of glycogen-like granules was restored, and immunoelectron microscopy indicated that HSP70 was associated with the organelles of the Müller cells. Taken together, these data suggest that HSP70 in Müller cells plays a role in accommodation to stress.