title: Effect of low frequency stimulation of perforant path on kindling rate and synaptic transmission in the dentate gyrus during kindling acquisition in rats.
abstract: Low frequency stimulation (LFS) has an inhibitory effect on kindling acquisition. In the present study the effect of the perforant path LFS on induction of rapid perforant path kindled seizures and synaptic transmission in the dentate gyrus was investigated. Animals were kindled by perforant path stimulation in a rapid kindling manner (12 stimulations per day). In one group of animals LFS (0.1 ms pulse duration at 1 Hz, 200 pulses, and 50-150 microA) was applied to perforant path, immediately after termination of each rapid kindling stimulation. Application of LFS significantly retarded the kindling acquisition and increased the number of stimulations to achieved different kindled seizure stages. LFS also prevented an increment in the slope of field excitatory postsynaptic potentials and population spike amplitude during kindling. In addition, LFS significantly reduced the marked increase in early (10-50 ms intervals) and late (300-1000 ms intervals) paired-pulse depression induced by kindling. According to obtained results, it may be suggested that LFS of perforant path has a significant antiepileptogenic effect through inhibition of synaptic transmission in dentate gyrus. Meanwhile, LFS prevents an increase in the paired-pulse depression during kindling acquisition.
authors.affiliation: Department of Physiology, School of Medical Sciences, Tarbiat Modares University, Tehran, Islamic Republic of Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Mohammad-Zadeh
authors.forename: Javad
authors.initials: J
authors.lastname: Mirnajafi-Zadeh
authors.forename: Yaghoub
authors.initials: Y
authors.lastname: Fathollahi
authors.forename: Mohammad
authors.initials: M
authors.lastname: Javan
authors.forename: Parviz
authors.initials: P
authors.lastname: Ghorbani
authors.forename: Mehdi
authors.initials: M
authors.lastname: Sadegh
authors.forename: Seyed Mohammad
authors.initials: SM
authors.lastname: Noorbakhsh
mesh_terms: D000818:Animals; D018891:Dentate Gyrus / Q000502:physiology*; D004558:Electric Stimulation; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D007696:Kindling, Neurologic / Q000502:physiology*; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D019580:Perforant Pathway / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D009435:Synaptic Transmission / Q000502:physiology*