Kindling Epileptogenesis in Orbital and Mesial Frontal Cortical Areas of Subhuman Primates

Abstract

Despite ready bilateralization of ictal and interictal EEG discharge throughout cortical kindling, the rate of convulsive seizure development was slow at both orbital and mesial frontal sites, even in the epileptic baboon. However, convulsive generalization occurred swiftly from the mesial frontal cortical (MF) sites once conjugate head, eye, and body adversion developed in the three primate species examined. Only epileptic baboons developed Stage 5 bisymmetrical and bisynchronous convulsion. Stimulation of the contralateral homotopic mesial cortical site readily produced afterdischarge that remained localized and convulsive seizure development did not occur. The findings suggest that (a) the frontal lobe plays an important role in the generation of nonconvulsive seizures, (b) the frontorolandic cortex plays a unique role in convulsive seizure generalization, (c) the role of the intrinsic (genetic) factor is significant in determining the quality of the kindled seizure, and (d) the development of focal epileptogenesis at one MF site interferes with clinical seizure development at the "mirror focus." Our findings underscore (a) the necessity of the conceptual differentiation between the EEG mirror focus and the epileptogenic focus capable of generating clinical seizures and (b) the importance of dissecting interictal behavior reflecting a "continuous disorder of neuronal function," which may cause symptoms other than seizures.

Modeling epileptogenesis and temporal lobe epilepsy in a non-human primate

“…On the other hand, in rodent models of TLE with few hippocampal changes, such as the kindling model, SRS are either rare, taking weeks to start (Pinel, 1981). Similarly, in kindled primates, SRS developed only after several months of electrical stimulation (Wada et al, 1985;Wada and Osawa, 1976). The development of SRS and brain damage restricted mainly to the hippocampus and limbic structures are the major differences between our study and others that attempted to develop animal models of TLE using non-human primates (Gunderson et al, 1999;Soper et al, 1978;Wada and Osawa, 1976;Wada et al, 1974).…”

Motor Cortical Kindling in Cats: A Comparison of Adult Cats and Kittens

“…AD duration, frequency, and propagation ADS appeared both in stimulated motor cortex and in the contralateral homologous site during and after the first stimulation, consistent with previous cortical kindling studies (Wake and Wada, 1975;Majkowski et al, 1981;Wada et al, 1985). Our results showed that duration of ADS did not increase even before GTC occurred, as has been reported in premotor kindling (Wake and Wada, 1975 kowski et al (1981) reported no definite tendency in duration of ADS, although some animals showed increase of AD duration.…”

Ictal perfusion changes associated with seizure progression in the amygdala kindling model in the rhesus monkey

“…Most of our understanding about epileptogenesis and epilepsy comes from animals models in rodents . Only a few animal studies concerning epileptogenesis have been conducted in nonhuman primates …”

“…3 Only a few animal studies concerning epileptogenesis have been conducted in nonhuman primates. [4][5][6][7][8] Electrical kindling of the amygdala has been proposed as a model for mesial temporal lobe epileptogenesis. Electrical kindling is defined as the phenomenon whereby repeated administration of an initially subconvulsive electrical stimulus results in progressive intensification of seizure activity, culminating in a generalized seizure.…”