The effects of RDX on neuronal signaling in the basolateral amygdala and on the in vivo electrographic profile of a rodent
Logan, TT; Qashu, F; Pidoplichko, V; Bannon, D; Williams, L; Aroniadou-Anderjaska, V; Braga, MF
HERO ID
1065806
Reference Type
Journal Article
Year
2009
Language
English
| HERO ID | 1065806 |
|---|---|
| In Press | No |
| Year | 2009 |
| Title | The effects of RDX on neuronal signaling in the basolateral amygdala and on the in vivo electrographic profile of a rodent |
| Authors | Logan, TT; Qashu, F; Pidoplichko, V; Bannon, D; Williams, L; Aroniadou-Anderjaska, V; Braga, MF |
| Journal | Society for Neuroscience Abstract Viewer and Itinerary Planner |
| Volume | 39 |
| Page Numbers | 17-21 |
| Abstract | RDX is an explosive compound widely used by the military and is the main component of the plastic explosive composition C-4. RDX has been detected as a soil and groundwater contaminant at some Army training facilities. In humans, toxic ingestion or exposure to RDX has caused headache, dizziness, vomiting, confusion, and seizures. However, the mechanism(s) of RDX-induced seizures are not understood. Early behavioral studies speculated that RDX seizures originated in the limbic system, possibly in the amygdala. Thus, our studies began by investigating the electrophysiological effects of RDX on the basolateral nucleus of the amygdala (BLA), the nucleus that is most susceptible to seizurogenic insults. First, we confirmed that RDX administration (75 mg/kg, orally) in male Sprague Dawley rats (275-325g) rapidly caused generalized seizures in vivo, by recording cortical electrographic activity using screw electrodes bilaterally over the frontal and parietal cortices. Next, using whole-cell recordings in the voltage-clamp mode, in in vitro brain slices from 14-21 day-old, male Sprague Dawley rats, GABAA receptor-mediated spontaneous inhibitory post-synaptic currents (sIPSCs) were recorded from pyramidal-shaped neurons in the BLA, in the presence of 50 μM D-APV, 50 μM GYKI 53655, and 10 μM SCH50911 to block NMDA, AMPA, and GABAB currents, respectively. Upon application of 30μM RDX, the amplitude, but not frequency, of sIPSCs was markedly reduced. Subsequent application of 10 μM bicuculline completely blocked the sIPSCs, confirming that the currents which were reduced by RDX were mediated by GABAA receptors. We are now constructing a dose-response curve for the effect of RDX on the sIPSCs, as well as for the effect of RDX on IPSCs evoked by local pressure application of variable concentrations of GABA. The reduction of GABAA receptor-mediated currents by RDX in the BLA may be an important mechanism in the generation of seizure activity upon RDX ingestion or exposure. |
| Is Certified Translation | No |
| Dupe Override | No |
| Conference Location | Chicago, IL |
| Conference Name | 39th Annual Meeting of the Society-for-Neuroscience |
| Conference Date | October 2009 |
| Is Public | Yes |
| Language Text | English |
| Is Qa | No |