Background
Brattleboro rats (BRATs) have natural deficits in prepulse inhibition (PPI) of the
startle response similar to those exhibited by schizophrenia patients, which are reversed
by antipsychotics. We sought to determine whether they also have increases in striatal
dopamine-2 (D2) receptors found in some studies examining the brains of schizophrenia
patients.
Methods
Several days after startle testing, the brains of BRAT and Long Evans (LE) rats were
removed, and D1 and D2 receptor levels were measured by autoradiography.
Results
PPI was lower in BRATs consistent with previous reports. D2, but not D1, receptor
binding was significantly higher in the nucleus accumbens shell and the dorsomedial
caudate of BRAT compared with LE rats, consistent with some findings in schizophrenia
patients. Furthermore, individual rat PPI was inversely correlated with D2 binding
density.
Conclusions
These findings suggest that the dopamine system in BRATs is dysregulated and these
abnormalities may contribute to the PPI deficits observed in these rats.
Key Words
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Article info
Publication history
Published online: June 29, 2006
Accepted:
March 31,
2006
Received in revised form:
March 20,
2006
Received:
January 31,
2005
Identification
Copyright
© 2006 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
