TY - JOUR
T1 - Paravalbumin deficiency affects network properties resulting in increased susceptibility to epileptic seizures
AU - Schwaller, B
AU - Tetko, IV
AU - Tandon, P
AU - Silveira, DC
AU - Vreugdenhil, Martin
AU - Henzi, T
AU - Potier, M-C
PY - 2004/1/1
Y1 - 2004/1/1
N2 - Networks of GABAergic interneurons are of utmost importance in generating and promoting synchronous activity and are involved in producing coherent oscillations. These neurons are characterized by their fast-spiking rate and by the expression of the Ca2+-binding protein parvalbumin (PV). Alteration of their inhibitory activity has been proposed as a major mechanism leading to epileptic seizures and thus the role of PV in maintaining the stability of neuronal networks was assessed in knockout (PV-/-) mice. Pentylenetetrazole induced generalized tonic-clonic seizures in all genotypes, but the severity of seizures was significantly greater in PV-/- than in PV+/+ animals. Extracellular single-unit activity recorded from over 1000 neurons in vivo in the temporal cortex revealed an increase of units firing regularly and a decrease of cells firing in bursts. In the hippocampus, PV deficiency facilitated the GABA(A)ergic current reversal induced by high-frequency stimulation, a mechanism implied in the generation of epileptic activity. We postulate that PV plays a key role in the regulation of local inhibitory effects exerted by GABAergic interneurons on pyramidal neurons. Through an increase in inhibition, the absence of PV facilitates synchronous activity in the cortex and facilitates hypersynchrony through the depolarizing action of GABA in the hippocampus. (C) 2004 Elsevier Inc. All rights reserved.
AB - Networks of GABAergic interneurons are of utmost importance in generating and promoting synchronous activity and are involved in producing coherent oscillations. These neurons are characterized by their fast-spiking rate and by the expression of the Ca2+-binding protein parvalbumin (PV). Alteration of their inhibitory activity has been proposed as a major mechanism leading to epileptic seizures and thus the role of PV in maintaining the stability of neuronal networks was assessed in knockout (PV-/-) mice. Pentylenetetrazole induced generalized tonic-clonic seizures in all genotypes, but the severity of seizures was significantly greater in PV-/- than in PV+/+ animals. Extracellular single-unit activity recorded from over 1000 neurons in vivo in the temporal cortex revealed an increase of units firing regularly and a decrease of cells firing in bursts. In the hippocampus, PV deficiency facilitated the GABA(A)ergic current reversal induced by high-frequency stimulation, a mechanism implied in the generation of epileptic activity. We postulate that PV plays a key role in the regulation of local inhibitory effects exerted by GABAergic interneurons on pyramidal neurons. Through an increase in inhibition, the absence of PV facilitates synchronous activity in the cortex and facilitates hypersynchrony through the depolarizing action of GABA in the hippocampus. (C) 2004 Elsevier Inc. All rights reserved.
UR - http://www.scopus.com/inward/record.url?scp=1842638739&partnerID=8YFLogxK
U2 - 10.1016/j.mcn.2003.12.006
DO - 10.1016/j.mcn.2003.12.006
M3 - Article
C2 - 15080894
VL - 25
SP - 650
EP - 663
JO - Molecular and Cellular Neuroscience
JF - Molecular and Cellular Neuroscience
ER -