Kindling with rapidly recurring hippocampal seizures

Bipolar electrodes, stereotactically implanted in the hippocampus of adult rats, were used to deliver 10 s trains of suprathreshold tetanic electrical stimuli every few minutes. As indices of seizure intensity, durations of the afterdischarges triggered by these stimuli were measured, and the accompanying behaviors were scored on a 5-point scale. After 2-3 h, prolonged afterdischarges appeared in conjunction with severe limbic seizures, separated by periods of approximately 60 min. After 3-9 h, the stimulation was withheld until the following day. Upon reinstitution of the stimuli, intense seizures were seen at the onset, and the cycle time between them was shortened. Enhanced responsiveness to a fixed stimulus persisted for several months, the longest period tested. In addition, the enhanced epileptogenicity showed transference and was not stimulus-specific. These studies, using stimuli with low intertrain frequency and short interstimulus intervals, establish a robust and rapidly-developing model of epileptogenesis in the hippocampus that is comparable to traditional kindling.

[1]  R. Racine,et al.  Rates of motor seizure development in rats subjected to electrical brain stimulation: strain and inter-stimulation interval effects. , 1973, Electroencephalography and clinical neurophysiology.

[2]  J. Pinel,et al.  Postseizure inhibition of kindled seizures , 1977, Experimental Neurology.

[3]  M. E. Corcoran,et al.  Kindling of seizures with low-frequency electrical stimulation , 1980, Brain Research.

[4]  S. Feldblum,et al.  Role of the amygdala in development of hippocampal kindling in the rat , 1983, Experimental Neurology.

[5]  R. Sainsbury,et al.  Electrically induced seizure activity in the hippocampus: time course for postseizure inhibition of subsequent kindled seizures. , 1978, Behavioral biology.

[6]  R. Racine,et al.  Modification of seizure activity by electrical stimulation. II. Motor seizure. , 1972, Electroencephalography and clinical neurophysiology.

[7]  G. V. Goddard.  The kindling model of epilepsy , 1983, Trends in Neurosciences.

[8]  R. Racine.  Modification of seizure activity by electrical stimulation. I. After-discharge threshold. , 1972, Electroencephalography and clinical neurophysiology.

[9]  R. Racine.  Kindling: the first decade. , 1978, Neurosurgery.

[10]  Mitsumoto Sato.  Hippocampal Seizure and Secondary Epileptogenesis in the “Kindled” Cat Preparations , 1975, Folia psychiatrica et neurologica japonica.

[11]  A. Phillips,et al.  Effects of current intensity on kindled motor seizure activity in rats. , 1974, Behavioral biology.

[12]  W. Burnham,et al.  Development of a New Pharmacological Seizure Model: Effects of Anticonvulsants on Cortical‐and Amygdala‐Kindled Seizures in the Rat , 1980, Epilepsia.

[13]  R. C. Collins,et al.  Kainic acid‐induced limbic seizures , 1981, Neurology.

[14]  R. Racine,et al.  First trial motor seizures triggered by amygdaloid stimulation in the rat. , 1973, Electroencephalography and clinical neurophysiology.

[15]  N. Yamaguchi,et al.  Development of kindling in acute experiments and serial changes of field excitatory and inhibitory post-synaptic potentials during the ‘acute kindling’ , 1981, Brain Research.

[16]  M. Sato,et al.  A study of psychomotor epilepsy with "kindled" cat preparations. , 1976, Folia psychiatrica et neurologica japonica.

[17]  T. Albertson,et al.  Intertrial intervals and kindled seizures , 1981, Experimental Neurology.

[18]  J. McNamara,et al.  The kindling model of epilepsy: A review , 1980, Progress in Neurobiology.

[19]  J. Delgado,et al.  Evolution of repeated hippocampal seizures in the cat , 1961 .

[20]  R. C. Collins,et al.  Kainic acid induced limbic seizures: metabolic, behavioral, electroencephalographic and neuropathological correlates , 1981, Brain Research.

[21]  C. Zorumski,et al.  Functional mapping of limbic seizures originating in the hippocampus: a combined 2-deoxyglucose and electrophysiologic study , 1985, Brain Research.

[22]  K. Taber,et al.  Status epilepticus: a new rodent model. , 1977, Electroencephalography and Clinical Neurophysiology.

[23]  D. Mcintyre,et al.  Effects of amygdala lesions on dorsal hippocampus kindling in rats , 1982, Experimental Neurology.

[24]  G. V. Goddard,et al.  A permanent change in brain function resulting from daily electrical stimulation. , 1969, Experimental neurology.

[25]  R. Racine,et al.  Afterdischarge Thresholds and Kindling Rates in Dorsal and Ventral Hippocampus and Dentate Gyrus , 1977, Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques.