The overarching aim of thisgrant is to examine the role of glutamatergic neurotransmission,in particular that ofjgiutamatergic efferents rom the prefrontal cortex (RFC), in the functional abnormalities that may be ?elated to schizophrenia.One of our key findings during the past funding period has been that NMDA receptor hypofunction in b having animals increases the firing of RFC pyramidal cells consistent with the idea that cortical GABAint irneurons have a high level of NMDA tonic activation that drives the pyramidal neurons. Based on this progress, it is hypothesized that NMDA receptor hypofunction reduces the inhibitory influence of GABA interneurons on cortical pyramidal cells producing a tonic state of disinhibition at these neurons. We predict that tr is reduced inhibitory control (1) diminishes the capacity of RFC neurons to fire appropriately to task relevant stimuli, and (2) exaggeratesthe phasic impact of glutamate afferentson some pyramidal neurons leading to abnormal activity of RFC projections to dopamine cells resulting in excess dopamine release.The first prediction assumes a constant state of aberration, consistentwithsustained cognitive deficits in schizof: hrenia. The second prediction assumes interrupted changes in dopamine release th^t occur in response to p lasic activationof afferents from regions such as the thalamus and habenula consistent with episodic incidents of psychosis in schizophrenia. We further hypothesize that events at the excitatory afferent-GABAsynapse in the RFC are key for discovering drug targetsthat normalize the impact of jthe reduced inhibitory central on RFC efferents and, hence, may be useful for treatment of schizophrenia. We propose to test these hypotheses using ensemble recording and mierodialysis in behaving rodents. Public health relevance schizophrenia is a major public health concern. This project seeks to develop anew understanding of the pathophysiology of schizophrenia and evaluate novel treatment options for treatment of this disorder.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37MH048404-19
Application #
7659703
Study Section
Special Emphasis Panel (NSS)
Program Officer
Winsky, Lois M
Project Start
1992-09-15
Project End
2013-06-30
Budget Start
2009-07-01
Budget End
2010-06-30
Support Year
19
Fiscal Year
2009
Total Cost
$377,373
Indirect Cost
Name
University of Pittsburgh
Department
Neurosciences
Type
Schools of Arts and Sciences
DUNS #
004514360
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213
Lohani, Sweyta; Martig, Adria K; Underhill, Suzanne M et al. (2018) Burst activation of dopamine neurons produces prolonged post-burst availability of actively released dopamine. Neuropsychopharmacology 43:2083-2092
Lohani, S; Poplawsky, A J; Kim, S-G et al. (2017) Unexpected global impact of VTA dopamine neuron activation as measured by opto-fMRI. Mol Psychiatry 22:585-594
Park, Junchol; Wood, Jesse; Bondi, Corina et al. (2016) Anxiety Evokes Hypofrontality and Disrupts Rule-Relevant Encoding by Dorsomedial Prefrontal Cortex Neurons. J Neurosci 36:3322-35
Simon, Nicholas W; Moghaddam, Bita (2015) Neural processing of reward in adolescent rodents. Dev Cogn Neurosci 11:145-54
Simon, Nicholas W; Gregory, Timothy A; Wood, Jesse et al. (2013) Differences in response initiation and behavioral flexibility between adolescent and adult rats. Behav Neurosci 127:23-32
Volman, Susan F; Lammel, Stephan; Margolis, Elyssa B et al. (2013) New insights into the specificity and plasticity of reward and aversion encoding in the mesolimbic system. J Neurosci 33:17569-76
Totah, Nelson K B; Jackson, Mark E; Moghaddam, Bita (2013) Preparatory attention relies on dynamic interactions between prelimbic cortex and anterior cingulate cortex. Cereb Cortex 23:729-38
Matthews, Marguerite; Bondi, Corina; Torres, Gonzalo et al. (2013) Reduced presynaptic dopamine activity in adolescent dorsal striatum. Neuropsychopharmacology 38:1344-51
Totah, Nelson K B; Kim, Yunbok; Moghaddam, Bita (2013) Distinct prestimulus and poststimulus activation of VTA neurons correlates with stimulus detection. J Neurophysiol 110:75-85
Wood, Jesse; Kim, Yunbok; Moghaddam, Bita (2012) Disruption of prefrontal cortex large scale neuronal activity by different classes of psychotomimetic drugs. J Neurosci 32:3022-31

Showing the most recent 10 out of 31 publications