Specific expression of galanin in the peri-infarct zone after permanent focal cerebral ischemia in the rat

Galanin (Gal) is a neuropeptide with supposed neurotrophic-like action. In the present study, expression of Gal has been investigated in the core and peri-infarct zone at 1, 4, 24 and 72 h after middle cerebral artery occlusion (MCAo) in the rat. Three days after MCAo a small but consistent number of morphological intact Gal-positive neuronal cells were observed in the peri-infarct zone. Gal-positive cells were barely detectable in the infarct and peri-infarct zone at 24 h. No Gal immunopositive cells were detected in brain subjected to 1 and 4 h of ischemia. Gal immunoreactivity was also detected in myelinated fibers 4 and 24 h after focal ischemia.Gal may be a peptide with neurotrophic and plasticity functions under stress conditions.