Intrahippocampal cholinergic-rich transplants restore lead-induced deficits: a preliminary study in rats

In the present study restorative potential of fetal cholinergic rich cell s uspensions in ameliorating cognitive deficits in rats perinatally exposed t o lead was studied. Lactating dams with 1-day old litters were given 0.2% ( w/v) lead acetate in drinking water throughout lactation from postnatal day (PND) 1 to PND21 at the end of which the treatment was stopped and the ani mals were weaned. On PND42 lead exposed rats were given bilateral, intrahip pocampal, cholinergic rich fetal neural transplants (approximately 60,000 c ells per site) and subsequently assessed 3 and 6 months posttransplantation . Control animals (Sham operated and transplanted) were also run in paralle l. Lead exposed rats exhibited a decreased learning ability and locomotor a ctivity. A significant decrease in the levels of acetylcholinesterase and s odium potassium ATPase Na+,K+-ATPase activity was observed in hippocampal r egion of lead exposed rats. The levels of lead were increased by fivefold i n the hippocampal region of lead exposed rats. Transplantation showed margi nal improvement in the above impairments at 3 months which were more marked at 6 months. Lead levers at 6 months were not significantly higher in lead exposed rats as compared with the control. Results confirm previous findin gs that fetal neural transplants help in restoring the lost functional defi cits and demonstrate their restorative potential in case of lead induced de ficits. (C) 1999 Elsevier Science Inc. All rights reserved.