Audiogenic seizure

In mice, PCP is effective in antagonizing electroshock- or pentylenetetrazol (PTZ)-induced tonic extensor convulsions and audiogenic seizures (Chen et al. 1959 Chen and Bohner 1961). In dogs,... 

Exposure to doses below the level that will produce seizures can result in long-lasting central nervous system sensitization such as an increased susceptibility to sound induced (audiogenic) seizures. 

Zinc is important to the normal functioning of the central nervous system (CNS). At low concentrations, zinc protects mammalian brain neurons by blocking N-methyl-D-aspartate receptor-mediated toxicity. At high concentrations, zinc is a potent, rapidly acting neurotoxicant in the mammalian brain, as judged by zinc-induced neuronal injury of in vitro mature cortical cell cultures (Choi et al. 1988). Increased brain levels of zinc are associated with Pick s disease in certain strains of rodents with inherited epileptic seizures. Intravenous injection of zinc in rats with genetically inherited epilepsy produces seizures a similar response occurs with intracranial injection of zinc in rabbits with inherited audiogenic seizures (Choi et al. 1988). 

Herberg LJ, Watkins PJ Epileptiform seizures induced by hypothalamic stimulation in the rat, resistance to fits following fits. Nature 209 515-516, 1966 Herberg LJ, Tress KH, Blundell JE Raising the threshold in experimental epilepsy by hypothalamic and septal stimulation and by audiogenic seizures. Brain 92 313-328, 1969... 

De Sarro, G., Di Paola, E. D., Conte, G., Pasculli, M. P., De Sarro, A. Influence of retigabine on the anticonvulsant activity of some antiepileptic drugs against audiogenic seizures in DBA/2 mice, Naunyn-Schmiedeberg s Archiv of Pharmacology 2001, 363, 330-336. 

Blockade of the 5-HT7 receptor has been shown to reduce epileptic activity in animal models. Audiogenic seizures induced in DBA/2J mice could be prevented by drugs in a rank order of potency corresponding to their affinity for the 5-HT7 receptor (95). The selective 5-HT7 receptor antagonist SB-258719 has been shown to reduce epileptic activity in an animal model for absence epilepsy, the WAG/Rij rat (65). It is believed to do so by modulating the pacemaker current Ih within the thalamus (96,97). The 5-HT7 receptor has been demonstrated to mediate depolarization within the anterodorsal thalamus by increasing lh through a cAMP-dependent, PKA-independent mechanism (96,97). 

ICgo = 0.67 ijlM), with anticonvulsant activity (ED = 6 mg/kg) in the audiogenic seizure model (8) as well as possessing significant analgesic activity. 

Kilimov, N., Effect of Nivalin on audiogenic seizures in mice, Dokl. Bulg. Acad. NauL, 18, 287, 1965. 

The following abbreviations are used in the present review THC (tetrahydrocannabinol) CBD (cannabidiol) CBN (cannabinol) DMH (1,1-dimethylheptyl) SAR (structure-activity relationship) cisplatin (m-diam-minedichloroplatinum(II)) GABA (y-aminobutyric acid) MES (maximal electroshock seizures) PTZ (pentylenetetrazol) AGS (audiogenic seizure) IOP (intraocular pressure). 

The anticonvulsant SAR of CBD-type compounds bears no relationship to either the cannabimimetic or the anticonvulsant activity of THC-type compounds. As mentioned above, CBD itself, which is non-cannabimimetic in animal tests as well as in humans, exhibits significant activity in the MES test [ 178-180]. The CBD derivatives (44), (45) and (46) were equiactive with CBD [179]. Unexpectedly, the unnatural (+ )-enantiomer of CBD (47) was also shown to be at least as active as natural CBD in the MES test [ 180]. The DMH homologues of both (- )-CBD and (+ )-CBD were several times more active than CBD [180]. These and numerous other side-chain homologues of (+ )-and (- )-CBD were also shown to be active in audiogenic seizure susceptible (AGS) rats [ 181 ]. These observations are particularly striking since the unnatural (+ )-enantiomer of THC as well as its DMH homologue (38) are much less active than natural (- )-A -THC in such rats. The highly purified, crystalline (+ )-7-hydroxy-A6-THC-DMH (33) is completely inactive in the AGS rats, while the (- )-enantiomer (32) is extremely potent [106]. 

Some recent observations have underlined the necessity of interpreting with caution the results of experiments which have sought to modify GABA metabolism. Animals habituated to, and then withdrawn from, barbiturate drugs, develop (as do human beings) spontaneous convulsions or an increased susceptibility to audiogenic seizures . It was shown by Essig that these... 

AUD ss Anticonvulsant activity against audiogenic seizures in animals... 

N. D. Byington, Flow Injection Atomic Absorption Assay of Copper and Zinc in the Plasma of Age Dependent Audiogenic Seizure Susceptible Mice. Diss. Ahstr. Int. B, 43 (1983) 3228. 

With respect to experimental studies in rats born from mothers with severe iodine deficiency, several neurological abnormalities have been demonstrated. The progeny has susceptibihty to audiogenic seizures, associated with irreversible hearing defects, similar to those found in neurological cretinism. Several areas of the brain, such as the cerebral cortex, hippocampus and cerebellum, present morphological abnormalities (Martinez-Galan et al, 1997). 

Van Middlesworth, L, Audiogenic seizures in rats after severe prenatal and perinatal iodine depletion. Endocrinology 100 242 (1977)... 

Van Middlesworth L, Norris CH, Audiogenic seizures and cochlear damage in rats after perinatal antithyroid treatment. Endocrinology 106 1686 (1980)... 

Finally, it has been shown experimentally in animals that fetal hypothyroidism induces damage of the inner ear (64-68), which is possibly responsible for the audiogenic seizures reported in the offspring of extremely severely iodine deficient rats (69). 

A higher concentration of ganglioside was found in the cerebrum and brain stem tissue of mice susceptible to audiogenic seizures than was found in resistant strains, but a lower concentration was found in the cerebellum. Of the individual gangliosides, a higher concentration of Gmi was found in all three regions of the brain of susceptible mice. 

Kawai, H, Allende, ML, Wada, R, Kono, M, Sango, K, Deng, C, Miyakawa, T, Crawley, JN, Werth, N, Bierfreund, U, Sandhoff, K and Proia, RL (2001) Mice expressing only monosialoganglioside GM3 exhibit lethal audiogenic seizures. J Biol Chem, 276, 6885-6888. 

In rats imipenem - - dlastin provoked convulsions dose dependently, with characteristic electroencephalographic changes [21 ]. Audiogenic stimulation did not by itself provoke seizures in untreated rats but did after pretreatment with imipenem however, these seizures were not accompanied by electroencephalographic changes. The authors proposed that imipenem-induced seizures involve neuronal networks in the cortex whereas audiogenic seizures involve networks in the brainstem. 

Zivanovic D, Stanojlovic O, Stojanovic J, Susie V. Induction of audiogenic seizures in imipenem/dlastatin-treated rats. Epilepsy Behav 2004 5 151-8. 

H. Laird and R. Huxtable, Effects of taurine on audiogenic seizure... 

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