Supranormal levels of serotonin and its metabolite after raphe cell transplantation in serotonin-denervated rat hippocampus.
Transplantation of fetal raphe cells (14 days of gestation) into the adult rat hippocampus, 2 weeks following serotonin (5-HT)-denervation with intracisternal injection of 5,7-dihydroxytryptamine, can restore 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels in the hippocampus to far beyond normal values. Transplantation into the unilateral hippocampus produces asymmetrical turning behavior after administration of the 5-HT releasor, p-chloroamphetamine (IP), comparable to the behavior reported for rats with 5-HT denervation of the unilateral hippocampus. The effect is blocked by prior depletion of 5-HT with p-chlorophenylalanine (IP). The asymmetry in 5-HT levels are correlated with the behavioral change. These data indicate that a large amount of 5-HT is released from nerve terminals of transplanted raphe cells, and suggest that the supranormal levels of 5-HT and 5-HIAA after raphe cell transplantation are neurochemical correlates of 5-HT hyper-innervation of the hippocampus which has been reported previously.
D015116:5,7-Dihydroxytryptamine; D000818:Animals; D004298:Dopamine / Q000378:metabolism; D007839:Functional Laterality / Q000502:physiology; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D011903:Raphe Nuclei / Q000502:physiology / Q000637:transplantation*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism / Q000502:physiology*; D013239:Stereotyped Behavior / Q000502:physiology*
D015116:5,7-Dihydroxytryptamine; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D004298:Dopamine; D009638:Norepinephrine