VIRGOLINI MIRIAM BEATRIZ
Congresos y reuniones científicas
Título:
Stress-induced cocaine sensitization: changes in the actin cytoskeleton and in dendritic spines from prefrontal cortex
Autor/es:
ESPARZA A, BOLLATTI F, GARCIA KELLER C, VIRGOLINI M, LÓPEZ M, BRUSCO A, KALIVAS PW AND CANCELA L.M.
Lugar:
Chicago, Illinois, USA
Reunión:
Congreso; Society for Neuroscience. 39th Annual Meeting.; 2009
Institución organizadora:
Society for Neuroscience
Resumen:
STRESS-INDUCED COCAINE SENSITIZATION: CHANGES IN THE ACTIN CYTOSKELETON AND IN DENDRITIC SPINES FROM PREFRONTAL CORTEX.
Esparza A1*, Bollatti F1*, Garcia Keller C*, Virgolini M*, López M**, Brusco A**, Kalivas PW# and Cancela L.M*.
*IFEC-CONICET. Department of Pharmacology. School of Chemical Sciences. National University of Córdoba. Córdoba, Argentina. **IBYME-CONICET. School of Medicine. National University of Buenos Aires. Argentina. #Department of Neuroscience. Medical University of South Carolina, Charleston, SC, USA.
Drug addiction is associated with long-term changes in synaptic functionality. The proactive influence of stress on drug-addiction is exerted on excitatory synapses through the activation of common mechanisms between stress and drugs. This study was aimed to show whether the neurobiological mechanisms that modulate repeated-cocaine administration also occur in a chronic stress-induced cocaine sensitization model. Considering that F-actin is involved in the dendritic spine formation, it was evaluated whether chronic restraint stress induces alterations in actin rearrangement and in dendritic spines in prefrontal cortex. The number and density of spines (number of spines per µm2) was analyzed by electron microscopy, in 40 fields (42.52 µm2) for each animal of each experimental group. It was shown that chronic restraint stress induces a significant increase in F-actin levels in prefrontal cortex, which returned to baseline after cocaine administration. The polymerizing protein Arp2 was also increased while the depolymerizing p-cofilin was not modified after chronic stress. Postsynaptic density proteins such as homer and GluR1 were not changed after repeated stress and/or cocaine. The analysis of the number and density of spines in prefrontal cortex showed an increase after chronic stress, and a return to baseline values following stress and cocaine, similarly to that observed for F-actin. Our findings revealed that chronic stress induces changes in protein levels involved in synaptic plasticity, such as actin and proteins that regulate actin cytoskeleton, known as actin-binding proteins. It is highly probable that chronic stress-induced changes on F-actin and spines are associated with the cross-sensitization to cocaine.
Funded by ANPCyT BID 1728/OC ? AR PICT No 5-38081 and CONICET from Argentina. GluR1 and P-cofilin antibodies were kindly provided by P. Kalivas and J. Bamburg , respectively.
1Equal contribution
Esparza A1*, Bollatti F1*, Garcia Keller C*, Virgolini M*, López M**, Brusco A**, Kalivas PW# and Cancela L.M*.
*IFEC-CONICET. Department of Pharmacology. School of Chemical Sciences. National University of Córdoba. Córdoba, Argentina. **IBYME-CONICET. School of Medicine. National University of Buenos Aires. Argentina. #Department of Neuroscience. Medical University of South Carolina, Charleston, SC, USA.
Drug addiction is associated with long-term changes in synaptic functionality. The proactive influence of stress on drug-addiction is exerted on excitatory synapses through the activation of common mechanisms between stress and drugs. This study was aimed to show whether the neurobiological mechanisms that modulate repeated-cocaine administration also occur in a chronic stress-induced cocaine sensitization model. Considering that F-actin is involved in the dendritic spine formation, it was evaluated whether chronic restraint stress induces alterations in actin rearrangement and in dendritic spines in prefrontal cortex. The number and density of spines (number of spines per µm2) was analyzed by electron microscopy, in 40 fields (42.52 µm2) for each animal of each experimental group. It was shown that chronic restraint stress induces a significant increase in F-actin levels in prefrontal cortex, which returned to baseline after cocaine administration. The polymerizing protein Arp2 was also increased while the depolymerizing p-cofilin was not modified after chronic stress. Postsynaptic density proteins such as homer and GluR1 were not changed after repeated stress and/or cocaine. The analysis of the number and density of spines in prefrontal cortex showed an increase after chronic stress, and a return to baseline values following stress and cocaine, similarly to that observed for F-actin. Our findings revealed that chronic stress induces changes in protein levels involved in synaptic plasticity, such as actin and proteins that regulate actin cytoskeleton, known as actin-binding proteins. It is highly probable that chronic stress-induced changes on F-actin and spines are associated with the cross-sensitization to cocaine.
Funded by ANPCyT BID 1728/OC ? AR PICT No 5-38081 and CONICET from Argentina. GluR1 and P-cofilin antibodies were kindly provided by P. Kalivas and J. Bamburg , respectively.
1Equal contribution
