Article

A longitudinal examination of the neurodevelopmental impact of prenatal immune activation in mice reveals primary defects in dopaminergic development relevant to schizophrenia.

Laboratory of Behavioural Neurobiology, Swiss Federal Institute of Technology Zurich, 8603 Schwerzenbach, Switzerland.
Journal of Neuroscience (impact factor: 7.11). 01/2010; 30(4):1270-87. DOI:10.1523/JNEUROSCI.5408-09.2010 pp.1270-87
Source: PubMed

ABSTRACT Prenatal exposure to infection is a significant environmental risk factor in the development of schizophrenia and related disorders. Recent evidence indicates that disruption of functional and structural dopaminergic development may be at the core of the developmental neuropathology associated with psychosis-related abnormalities induced by prenatal exposure to infection. Using a mouse model of prenatal immune challenge by the viral mimic polyriboinosinic-polyribocytidilic acid, the present study critically evaluated this hypothesis by longitudinally monitoring the effects of maternal immune challenge during pregnancy on structural and functional dopaminergic development in the offspring from fetal to adult stages of life. Our study shows that prenatal immune challenge leads to dopaminergic maldevelopment starting as early as in the fetal stages of life and produces a set of postnatal dopaminergic abnormalities that is dependent on postnatal maturational processes. Furthermore, our longitudinal investigations reveal a striking developmental correspondence between the ontogeny of specific dopaminergic neuropathology and the postnatal onset of distinct forms of dopamine-dependent functional abnormalities implicated in schizophrenia. Prenatal immune activation thus appears to be a significant environmental risk factor for primary defects in normal dopaminergic development and facilitates the expression of postnatal dopamine dysfunctions involved in the precipitation of psychosis-related behavior. Early interventions targeting the developing dopamine system may open new avenues for a successful attenuation or even prevention of psychotic disorders following neurodevelopmental disruption of dopamine functions.

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Keywords

developing dopamine system
 
developmental neuropathology
 
distinct forms
 
dopamine functions
 
dopamine-dependent functional abnormalities
 
functional dopaminergic development
 
maternal immune challenge
 
normal dopaminergic development
 
postnatal dopamine dysfunctions
 
postnatal dopaminergic abnormalities
 
postnatal maturational processes
 
postnatal onset
 
Prenatal exposure
 
prenatal immune challenge
 
primary defects
 
Recent evidence
 
specific dopaminergic neuropathology
 
structural dopaminergic development
 
successful attenuation
 
viral mimic polyriboinosinic-polyribocytidilic acid