RESUMO
The receptor tyrosine kinase ErbB4 and its ligand trophic factors of the neuregulin (NRG) family have been associated with schizophrenia and other mental disorders in human genetic studies. In vivo studies in mice have shown how abnormal Nrg-ErbB4 signaling leads to deviant behaviors relevant to distinct aspects of schizophrenia, including hyperactivity, sensory gating deficits, working and spatial memory deficits and impaired social behavior. However, so far little is known on the role of ErbB4 in attention and inhibitory control, two aspects of executive functions that are impaired in schizophrenia. Here we investigated the effects of constitutive loss of ErbB4 in the central nervous system of mice on performance in a 5-choice serial reaction time task (5CSRTT) assessing attention and inhibitory control. In this task, ErbB4-/- mice did not show deficits in various parameters of attention, and premature responses as measure of inhibitory control. Nonetheless, ErbB4-/- mice recapitulated a specific set of behavioral phenotypes associated with schizophrenia, including a deficit in spatial learning and memory in the Barnes Maze and in contextual fear learning, and a trend for a deficit in sensorimotor gating. Furthermore, we investigated the effect of acute pharmacological inhibition of ErbB tyrosine kinase receptor using the pan-ErbB kinase inhibitor JNJ-28871063 (JNJ), in an automated version of the 5CSRTT. JNJ did not affect attention and inhibitory control. In conclusion, our data suggest no direct involvement of a classical Nrg-ErbB4 pathway in attention and inhibitory control in mice, while it confirms the involvement of this pathway in other domains relevant to schizophrenia.
