Housing conditions modulate the effects of intracerebral grafts in rats with brain lesions.
The aim of this study was to examine whether the behavioural effects of intracerebral grafts in rats with brain lesions can be modulated by postoperative housing conditions. Sixty-six young adult female rats were used. Twenty-two rats were sham-operated (S) and 44 rats sustained a complete aspirative lesion (L) of the fimbria-fornix and overlying tissue. The cavity was used in half the rats as the implantation site for solid fetal septal transplants (LT). Two days later, half the rats of each group were housed in an 'enriched' condition (S.EC, L.EC and LT.EC); the other half remained in standard condition (S.SC, L.SC and LT.SC). Two and 10 months later, the rats were tested in a Hebb-Williams maze. Two months after surgery, there was a highly significant lesion effect, no graft effect and no environmental effect except in S rats, S.EC rats making fewer initial errors than S.SC rats. Ten months after surgery, L rats still made more errors than S rats and S.EC rats made fewer initial errors than S.SC rats; however, the lesion-induced deficits were significantly attenuated in LT.EC rats, but not in LT.SC rats. These data show that both the enriched environment and the implant were unable alone to promote behavioural recovery but, applied together, they reduced the lesion-induced deficits. Dorsal hippocampus acetylcholinesterase (AChE)-staining intensity was reduced by the lesions, but this reduction was partially compensated for by the grafts; however, environmental conditions did not affect AChE-staining significantly. This latter observation suggests that the graft-derived partial cholinergic reinnervation of the hippocampus probably does not underly the behavioural improvement observed only in LT.EC rats.
Kelche
C
C
Laboratoire de Neurobiologie des Comportements, Université Louis Pasteur, Strasbourg, France.
Dalrymple-Alford
J C
JC
Will
B
B
D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001931:Brain Mapping; D004193:Discrimination Learning / Q000502:physiology; D005260:Female; D011939:Mental Recall / Q000502:physiology; D009416:Nerve Regeneration; D009434:Neural Pathways / Q000502:physiology; D009949:Orientation / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012686:Septal Nuclei / Q000502:physiology*; D012931:Social Environment
D000110:Acetylcholinesterase