Mode-dependent effect of low-frequency stimulation targeting the hippocampal CA3 subfield on amygdala-kindled seizures in rats.
Brain stimulation with low-frequency stimulation (LFS) is emerging as an alternative treatment for refractory epilepsy. The present study aimed to investigate the effects of LFS targeting the hippocampal CA3 subfield in different modes on amygdala-kindled seizures in Sprague-Dawley rats. When fully kindled seizures were achieved by daily electrical stimulation of the amygdala, LFS (15 min train of 0.1 ms pulses at 1 Hz and 100 microA) of the CA3 was applied in several modes. Post-treatment with LFS significantly reduced the severity of and susceptibility to evoked seizures, whereas pre-treatment with LFS resulted in a similar but much weaker inhibition of seizures. Interestingly, prior consecutive daily application of LFS in the absence of kindling stimulation did not reduce subsequent evoked seizures, but abolished the anti-epileptic effect of post-treatment. These results indicated that LFS of the CA3 is able to reduce kindled seizures in a mode-dependent manner without cumulative feature. The hippocampal CA3 subfield could be considered as a potential target for epilepsy treatment using LFS, and should be delivered in an appropriate stimulation mode.
Sun
Hong-Liu
HL
Institute of Neuroscience, School of Medicine, Department of Pharmacology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.
Zhang
Shi-Hong
SH
Zhong
Kai
K
Xu
Zheng-Hao
ZH
Zhu
Wei
W
Fang
Qi
Q
Wu
Deng-Chang
DC
Hu
Wei-Wei
WW
Xiao
Bo
B
Chen
Zhong
Z
D000679:Amygdala / Q000503:physiopathology*; D000704:Analysis of Variance; D000818:Animals; D001703:Biophysics / Q000379:methods*; D056654:CA3 Region, Hippocampal / Q000502:physiology*; D004195:Disease Models, Animal; D004599:Electric Stimulation Therapy / Q000379:methods*; D004569:Electroencephalography / Q000379:methods; D007696:Kindling, Neurologic / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000628:therapy*; D013997:Time Factors