TRANSGENIC MICE EXPRESSING THE HUMAN INDUCIBLE HSP70 HAVE HIPPOCAMPAL-NEURONS RESISTANT TO ISCHEMIC-INJURY

Using transgenic mice constitutively expressing the human inducible Hs p70, we examined the role of Hsp70 on cell survival after focal cerebr al ischemia. Twenty-four hours after permanent occlusion of the middle cerebral artery, no difference in infarct area was detected between H sp70-transgenic and non-transgenic mice. In the non-transgenic mice, m any pyramidal neurons of the ipsilateral hippocampus were observed to be pyknotic. However, in all Hsp70-transgenic mice, hippocampal pyrami dal neurons showed normal morphology and no evidence of pyknosis. This suggests that constitutive expression of Hsp70 reduces the extent of damage following permanent middle cerebral artery occlusion.