Naslov
Early and delayed effects of kainate application on oscillatory networks of the rat spinal cord in vitro.

Autori
Margaryan, G ; Taccola, G ; Mladinić Pejatović, Miranda ; Nistri, A.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
FENS Abstr., vol.4, 090.24 / - , 2008

Skup
6th FENS Forum of European Neuroscience

Mjesto i datum
Ženeva, Švicarska, 12.07.2008. - 16.07.2008

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Sensory and motor systems Spinal cord injury and plasticity

Sažetak
To test the functional and morphological consequences of excitoxicity on rhythmic patterns of spinal networks, 1 mM kainate (1 h) was applied to the isolated spinal cord of the neonatal rat. To assess any time dependent change in rhythmic spinal network activity, the preparation viability was checked in control conditions for 24 h by monitoring its electrophysiological properties that confirmed full ability to generate fictive locomotor patterns induced either electrically or chemically. Intrinsic rhythmicity of spinal networks (disinhibited bursting) evoked by strychnine and bicuculline was, however, slowed down. Histological examination of spinal cords kept in standard solution for 24 h showed well preserved cell populations comprising neurons and glia throughout the grey and white matters. One day after applying kainite, it was not possible to generate fictive locomotor patterns during repeated stimulus trains because of the strong reduction in polysynaptic transmission. Likewise, NMDA and serotonin co-application (even at higher doses) failed to induce alternating oscillations. Conversely, disinhibited bursting was still present even though it showed irregular periodicity and longer burst duration. Globally, these results indicate good survival of spinal networks for at least 24 h in vitro with electrophysiological and morphological characteristics analogous to those observed shortly after dissection. In conclusion, our results suggest that 1 h excitotoxic insult produced by a high concentration of kainate induced delayed differential effects on rhythmic patterns as fictive locomotion was abolished, yet disinhibited bursting remained. It is likely that excitotoxicity was translated in severe impairment of network synaptic transmission rather than extensive neuronal death.

Izvorni jezik
Engleski

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