Elevated cholecystokinin mRNA in dorsolateral prefrontal cortex in suicides

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Ab~tracts

IHOL PSYCHIATRY 1996:39:500-666

traccrs in the fronlal cortex (area 6M/8Bm or the medial prefrontal cortex), llnterior cuudatc nucleus (Cd) and the nucleus llccumbcns (Acb) of the same .mimal(s). Tr.lcing wa~ combined with tyrosine hydroxylase immunohistochemistry to identify midbrain dopamincrgic retrogrudclylabl!led neurons. Our results demonstrate II remarkable segregation of these DA projections: (I) DA neurons which project to the frontal cortex arc distinct from Ihose projecting to the Cd and the Acb. as no evidence of axonal collatemUzation was observed, and. the cortically projecting neurons were typically located tlorsally to Ihose with stritual targcts; (2) DA cells projecting 10 each of the target areas were founu to arise from more than one midbrain DA cell group (A9, A10, .::I.nd AS). NevenhC!lcss. the Acb receives its heaviesl DA input from A10 and nl«.:dial A9 DA neurons, while the caudate nucleus fCccives it" principal input from more lalerally located SN pars compacta DA neurons, anll (3) DA cells projecting 10 the Acb were segregated from those projecting to the Cd as cells containing two nuorochromes were never observed. The finding that DA cells projccting 10 the Fe, Acb ami Cd arc comflar1ment.::l.li~cd and exhibit little topographic o...erlap appears to accentuate a pallcm evident, but not fully re.::l.1izcd. in rodenL'I and provides an .::I.nalomical basis of functional autonomy among these projections in normal and abnonnal conditions. Supponcd by MII44866

446. SENSORY GATING IN A COMPUTER MODEL OF THE CA3 NEURAL NETWORK OF THE HIPPOCAMPUS

K.A. Flach:'!, G.A. Gerhardt l .:'!, R. Freedman l •2, & L.E. Adler l •3 Depls.or IPsychiatry and 2Ph:mnacolop. Uni...endty of Colorado Hcallh Sciences Center. Denver. CO: . Denver VAMC We have developed :l unique computer mollel of the CA3 region of Ihe hippocampus that simulates PSO auditory sensory gating. The PSO waVeform of the auditory evoked potential is decreased to (he second of two closely paired auditory click !itimuli in nonnal controls, but not in schizophrenic patients. Our computer modcl of the CA3 hipP0C3mpnl network includes recurrent nctivution from within the CA3 region liS well .::1.5 input from the cnlorhinal cor1cl( and the medial septal nucleus. Information in the model is represented by modified Hcbb ccllasscmbUes. We used the lllO