TY - JOUR
T1 - Divergent anatomical pattern of D-3 binding and DARPP-32 mRNA expression in the Roman strains: implications for vulnerability to drug addiction
T2 - Implications for drug addiction
AU - Guitart-Masip, M.
AU - Johansson, B.
AU - Fernández-Teruel, A.
AU - Cañete, T.
AU - Tobeña, A.
AU - Terenius, L.
AU - Giménez-Llort, L.
N1 - Funding Information:
This study was supported by grants from AFA (Stockholm, Sweden), Fundació Marató de TV3 014110, Programa Ramón y Cajal and Ericsson’s Foundation. The Medical Psychology Unit is the recipient of SGR-00071-2000 and SAF 2003-03480. M.G. received a predoctoral FI scholarship from Generalitat de Catalunya.
PY - 2006/11/3
Y1 - 2006/11/3
N2 - Autoradiography analysis of D1, D2 and D3 dopamine receptors and in situ hybridization analysis of mRNA for dopamine and cAMP regulated phosphoprotein of 32 kDa (DARPP-32) were performed in brains of naïve Roman high avoidance (RHA) and Roman low avoidance (RLA) inbred rats. These strains, genetically selected for high (RHA) or extremely low (RLA) active avoidance acquisition in the two-way shuttle box, differ in indices of dopaminergic activity along with sensation/novelty and substance-seeking behavioral profiles. The present study shows no differences in D2 receptor binding between the two strains. In contrast, the D1 and D3 receptor binding in the nucleus accumbens was higher in RHA-I rats, whereas RLA-I rats show higher D3 binding in the Calleja islands. Together with previous evidence showing behavioral and presynaptic differences related to the dopamine system, the present results suggest a higher dopaminergic tone at the nucleus accumbens shell in RHA-I rats. Besides, the comparison of the expression pattern of DARPP-32 mRNA with that of dopamine receptor binding revealed a mismatch in some amygdala nuclei. In some cortical structures (prelimbic and cingulate cortices, the dentate gyrus) as well as in the central amygdala, RHA-I rats showed higher DARPP-32 mRNA expression than RLA-I rats. Hence, RHA-I and RLA-I rats may be a useful tool to identify dopamine-related mechanisms that predispose to drug and alcohol dependence.
AB - Autoradiography analysis of D1, D2 and D3 dopamine receptors and in situ hybridization analysis of mRNA for dopamine and cAMP regulated phosphoprotein of 32 kDa (DARPP-32) were performed in brains of naïve Roman high avoidance (RHA) and Roman low avoidance (RLA) inbred rats. These strains, genetically selected for high (RHA) or extremely low (RLA) active avoidance acquisition in the two-way shuttle box, differ in indices of dopaminergic activity along with sensation/novelty and substance-seeking behavioral profiles. The present study shows no differences in D2 receptor binding between the two strains. In contrast, the D1 and D3 receptor binding in the nucleus accumbens was higher in RHA-I rats, whereas RLA-I rats show higher D3 binding in the Calleja islands. Together with previous evidence showing behavioral and presynaptic differences related to the dopamine system, the present results suggest a higher dopaminergic tone at the nucleus accumbens shell in RHA-I rats. Besides, the comparison of the expression pattern of DARPP-32 mRNA with that of dopamine receptor binding revealed a mismatch in some amygdala nuclei. In some cortical structures (prelimbic and cingulate cortices, the dentate gyrus) as well as in the central amygdala, RHA-I rats showed higher DARPP-32 mRNA expression than RLA-I rats. Hence, RHA-I and RLA-I rats may be a useful tool to identify dopamine-related mechanisms that predispose to drug and alcohol dependence.
KW - addiction
KW - amygdala
KW - dopamine receptors subtypes
KW - nucleus accumbens
KW - rodent models
UR - http://www.scopus.com/inward/record.url?scp=33750379955&partnerID=8YFLogxK
U2 - 10.1016/j.neuroscience.2006.07.041
DO - 10.1016/j.neuroscience.2006.07.041
M3 - Article
C2 - 17008016
SN - 0306-4522
VL - 142
SP - 1231
EP - 1243
JO - Neuroscience
JF - Neuroscience
IS - 4
ER -
