Neurotensin (NT), an endogenous tridecapeptide, is closely associated with CNS dopamine (DA) systems within the mammalian central nervous system (CNS). When administered directly into the CNS of laboratory animals, NT produces pharmacological, neurochemical and behavioral effects similar to those of antipsychotic drugs, particularly those classified as atypical. Typical antipsychotic drugs such as haloperidol increase NT concentrations and proNT mRNA expression in both the nucleus accumbens (a terminal area of the mesolimbic DA system) and the caudate nucleus (a terminal area of the nigroneostriatal DA system). Atypical antipsychotic drugs such as clozapine increase NT concentration and proNT mRNA expression only in the nucleus accumbens. These and other data suggest that the increase in these measures of NT biosynthesis in the nucleus accumbens are predictive of antipsychotic efficacy, whereas the increase in the caudate nucleus are predictive of extrapyramidal side effect (EPS) liability. There is also evidence that NT neuronal function is altered in schizophrenia. The present competitive renewal application seeks to focus on effects of typical and atypical antipsychotic drugs on the synaptic availability of NT in the nucleus accumbens and caudate nucleus, as well as on NT receptor kinetics and NT receptor mRNA expression. The intracellular signalling pathways mediating antipsychotic drug effects on c-fos and NT gene expression will be explored in primary neuronal cultures. Ontogeny and gender effects of antipsychotic drugs on NT neurons and on the CNS effects of NT will be scrutinized, a study of particular interest, in view of increasing evidence that schizophrenia is a neurodevelopmental disorder, and that there are gender differences in this disorder. We will study whether the behavioral effects of typical and atypical antipsychotics are mediated through NT receptor mechanisms. The brain sites of action of intracerebroventricularly administered NT will be mapped by fos immunohistochemistry. The electrophysiological effects of NT itself, and its actions on DA in the major subdivisions of the nucleus accumbens will be characterized. Signal transduction mechanisms mediating the effects of NT receptor activation will be explored in primary neuronal cultures. Finally, a major focus of the present proposal is assessing the role of NT neuronal system alterations in the pathophysiology of schizophrenia by measurement of various indices of NT neuronal function (NT, NT mRNA expression, NT receptor binding and NT receptor mRNA expression) in post- mortem brain tissue of patients who in life were diagnosed as schizophrenic, age- and sex-matched controls and a unique control group (patients with bipolar disorder treated with antipsychotic drugs). These studies will provide novel information concerning the role of NT systems in the mechanism of action of antipsychotic drugs, and in the pathophysiology of schizophrenia.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Research Project (R01)
Project #
5R01MH039415-16
Application #
2890323
Study Section
Special Emphasis Panel (SRCM (03))
Program Officer
Winsky, Lois M
Project Start
1983-12-01
Project End
2000-07-31
Budget Start
1999-08-01
Budget End
2000-07-31
Support Year
16
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Emory University
Department
Psychiatry
Type
Schools of Medicine
DUNS #
042250712
City
Atlanta
State
GA
Country
United States
Zip Code
30322
Chastain, Lucy G; Qu, Hongyan; Bourke, Chase H et al. (2015) Striatal dopamine receptor plasticity in neurotensin deficient mice. Behav Brain Res 280:160-71
Cáceda, Ricardo; Binder, Elisabeth B; Kinkead, Becky et al. (2012) The role of endogenous neurotensin in psychostimulant-induced disruption of prepulse inhibition and locomotion. Schizophr Res 136:88-95
Flandreau, Elizabeth I; Ressler, Kerry J; Owens, Michael J et al. (2012) Chronic overexpression of corticotropin-releasing factor from the central amygdala produces HPA axis hyperactivity and behavioral anxiety associated with gene-expression changes in the hippocampus and paraventricular nucleus of the hypothalamus. Psychoneuroendocrinology 37:27-38
Pariante, Carmine M; Nemeroff, Charles B (2012) Unipolar depression. Handb Clin Neurol 106:239-49
Martin, Elizabeth I; Ressler, Kerry J; Jasnow, Aaron M et al. (2010) A novel transgenic mouse for gene-targeting within cells that express corticotropin-releasing factor. Biol Psychiatry 67:1212-6
Gatt, Justine M; Williams, Leanne M; Schofield, Peter R et al. (2010) Impact of the HTR3A gene with early life trauma on emotional brain networks and depressed mood. Depress Anxiety 27:752-9
Gatt, Justine M; Nemeroff, Charles B; Schofield, Peter R et al. (2010) Early life stress combined with serotonin 3A receptor and brain-derived neurotrophic factor valine 66 to methionine genotypes impacts emotional brain and arousal correlates of risk for depression. Biol Psychiatry 68:818-24
Neigh, Gretchen N; Gillespie, Charles F; Nemeroff, Charles B (2009) The neurobiological toll of child abuse and neglect. Trauma Violence Abuse 10:389-410
Zeng, Fanxing; Mun, Jiyoung; Jarkas, Nachwa et al. (2009) Synthesis, radiosynthesis, and biological evaluation of carbon-11 and fluorine-18 labeled reboxetine analogues: potential positron emission tomography radioligands for in vivo imaging of the norepinephrine transporter. J Med Chem 52:62-73
Stein, Dan J; Cloitre, Marylene; Nemeroff, Charles B et al. (2009) Cape Town consensus on posttraumatic stress disorder. CNS Spectr 14:52-8

Showing the most recent 10 out of 113 publications