title: Cholinergic neural transplants into hippocampus restore learning ability in monkeys with fornix transections.
abstract: Monkeys with bilateral transections of the fornix were severely but selectively impaired at learning visuospatial conditional tasks presented in a Wisconsin General Test Apparatus. Bilateral transplantation of cholinergic-rich embryonic basal forebrain tissue into the hippocampus led to complete recovery from this specific learning impairment across a range of task difficulties. Administration of the direct cholinergic agonist pilocarpine to ungrafted animals immediately before testing also reduced this impairment, suggesting that the graft-associated recovery was mediated by acetylcholine release. Transection of the fornix produced a marked loss of acetylcholinesterase (AChE) staining confined to hippocampus and entorhinal cortex relative to controls. In all transplanted animals densely AChE-staining cellular masses were seen bilaterally in temporal lobe structures, with fibre outgrowth into surrounding host tissue.
authors.affiliation: Division of Psychiatry, Clinical Research Centre, Harrow, Middlesex, UK.
authors.forename: R M
authors.initials: RM
authors.lastname: Ridley
authors.forename: H D
authors.initials: HD
authors.lastname: Thornley
authors.forename: H F
authors.initials: HF
authors.lastname: Baker
authors.forename: A
authors.initials: A
authors.lastname: Fine
mesh_terms: D000110:Acetylcholinesterase / Q000032:analysis*; D000818:Animals; D016380:Brain Tissue Transplantation / Q000502:physiology*; D002143:Callitrichinae; D004192:Discrimination, Psychological; D004525:Efferent Pathways / Q000502:physiology*; D016332:Fetal Tissue Transplantation / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D007858:Learning / Q000502:physiology*; D008568:Memory; D012016:Reference Values; D013028:Space Perception
chemical_list: D000110:Acetylcholinesterase