Characterization and treatment of spontaneous recurrent seizures following nerve agent-induced status epilepticus in mice.

PURPOSE: To develop and characterize a mouse model of spontaneous recurrent seizures following nerve agent-induced status epilepticus (SE) and test the efficacy of existing antiepileptic drugs. METHODS: SE was induced in telemeterized male C57Bl6/J mice by soman exposure, and electroencephalographic activity was recorded for 4-6 weeks. Mice were treated with antiepileptic drugs (levetiracetam, valproic acid, phenobarbital) or corresponding vehicles for 14 d after exposure, followed by 14 d of drug washout. Survival, body weight, seizure characteristics, and histopathology were used to characterize the acute and chronic effects of nerve agent exposure and to evaluate the efficacy of treatments in mitigating or preventing neurological effects. RESULTS: Spontaneous recurrent seizures manifested in all survivors, but the number and frequency of seizures varied considerably among mice. In untreated mice, seizures became longer over time. Moderate to severe histopathology was observed in the amygdala, piriform cortex, and CA1. Levetiracetam provided modest improvements in neurological parameters such as reduced spike rate and improved histopathology scores, whereas valproic acid and phenobarbital were largely ineffective. CONCLUSIONS: This model of post-SE spontaneous recurrent seizures differs from other experimental models in the brief latency to seizure development, the occurrence of seizures in 100 % of exposed animals, and the lack of damage to CA4/dentate gyrus. It may serve as a useful tool for rapidly and efficiently screening novel therapies that would be effective against severe epilepsy cases.

Separating the "Limbs" of Yoga: Limited Effects on Stress and Mood.

Though millions of people practice yoga to reduce stress and improve their mood, it is unclear which aspect of yoga is responsible for these effects. To investigate relevant aspects, or "limbs" of yoga, participants who were novices in the practice of yoga engaged in a single yoga manipulation (i.e., poses, breath work, meditation, or listening to a lecture about yoga) for 20 min before experiencing a mild stressor. Participants' heart rate, blood pressure, mood, and anxiety level were assessed, both immediately after the yoga manipulation and after the mild stressor. The 20-min yoga manipulation did not differentially affect any of the measures, including participants' stress response after the mild stressor. Results are discussed regarding the individual components of a yoga practice.