Effects of Fetal Forebrain Transplants in Ibotenic-Injured Nucleus Basalis: An Anatomical Investigation

Abstract

Survival of fetal basal forebrain transplant (TP) into ibotenic-injured nucleus basalis of rats was examined after a delay between lesion and TP (1 or 2 weeks) and a delay between harvest and TP (1–4.5 hours). Optimal TP survival occured for TP made 2 weeks postlesion and less than 2 hours after harvesting. In these cases large, healthy TP-neurons displayed robust cytochrome oxidase (CO) activity and sent cholinergic processes throughout the TP and occasionally into host tissue. A mild astrocytic reaction was observed within the TP and at the host-TP interface. Surviving TPs increased choline acetyltransferase innervation and CO activity within the ipsilateral frontoparietal cortex. Therefore data suggest that fetal cholinergic TPs into the damaged NBM reduced neuronal degeneration within the NBM and stimulated remaining neurons spared by the lesion

Key Words:

• Basal forebrain transplant
• cholinergic markers
• astrocytes
• oxidative metabolism