Fast Fourier transformation analysis of kindling-induced afterdischarge in the XXXX hippocampus.

@entity410 @entity5 @entity95 @entity1315 @entity302
Kindling is a widely used animal model of intractable @entity1315 . In the present study, we performed fast Fourier transformation (FFT) analysis of kindling-induced afterdischarge (AD) in the @entity95 hippocampus. Ten adult @entity95 were used. Kindling stimulation to the right hippocampus was delivered as a train of biphasic pulses (1 ms duration each) of 50 Hz for 1s, with suprathreshold intensity for AD. Motor responses were classified into five stages according to the conventional criteria. Of 10 animals, five developed stage 5 @entity410 with a mean of 21 stimulations (kindled (K) group), while the remaining five animals did not (incomplete kindling (IK) group). We standardized each ratio of power spectral density of lower frequency band component (LFB: 0-9 Hz) and the higher frequency band (HFB: 12-30 Hz) in the initial stage as 1.0. The IK group exhibited small decrements (0.99 and 0.94 times) in LFB and HFB components at the final stage. In contrast, the K group exhibited a significantly (p<0.05) large decrement (0.49 times) in the LFB component and a very large increment (4.45 times) of HFB component at the final stage. Correlation analyses were performed between alteration of power spectral density ratio of the HFB component and AD duration, interictal discharge frequency, and behavioral stage during kindling progression. Fairly strong positive correlations were found in all cases in the K group. FFT analysis of kindling-induced AD demonstrated an important role of the HFB component: enhancement of the HFB component is associated with kindled stage, while decrement of it is associated with @entity5 . These findings suggest that FFT analysis of stimulus-induced and spontaneous @entity410 discharges is useful for examination of the progression of @entity302 .
