METHODS: Three extracts of ginger (Zingiber officinale) rhizome prepared by maceration using the respective solvents and 6-shogoal were reconstituted in normal saline with 0.2% DMSO. Thirty C57BL/6 15-week-old mice were divided into 5 groups: Group 1, saline; Group 2, 70% methanol extract; Group 3, 80% ethanol extract; Group 4, 100% DMSO extract; and Group 5, 6-shogaol. The baseline pilocarpine-stimulated salivary flow rate was measured at the age of 15 weeks (15th week), and treatment solutions were administered by intraperitoneal injection from the 16th to 18th week. The stimulated salivary flow rate during treatment weeks was recorded for each group, and its difference with baseline was analysed using paired-sample t test. The change in salivary flow rate between the treatment groups and the control group was analysed using one-way analysis of variance.
RESULTS: Groups 2, 3, 4, and 5 showed a significant increase in salivary flow rate when compared to baseline (P < .05). The increase in salivary flow rate in all 4 treatment groups was significant when compared to the control group (P < .05). Group 4 produced the highest increase in salivary flow rate; however, the differences amongst the treatment groups did not reach statistical significance (P > .05).
CONCLUSIONS: All GR extracts (70% methanol, 80% ethanol, 100% DMSO) and 6-shogaol were equally effective in increasing the pilocarpine-stimulated salivary flow rate in C57BL/6 mice when administered systemically as a sustained dose for 3 weeks.
Methods: Using a pilocarpine-induced epileptic mouse model, sensory-motor and visual cortical slices were prepared, and the whole-cell patch clamp technique was used to record spontaneous inhibitory post-synaptic currents (sIPSCs).
Results: The primary finding was that the mean amplitude of sIPSC from the sensory-motor cortex increased significantly in epileptic mice when the recording pipette contained MK-801 compared to control mice, whereas the mean sIPSC frequency was not significantly different, indicating that post-synaptic mechanisms are involved. However, there was no significant pre-synaptic inhibition through preNMDARs in the acute brain slices from pilocarpine-induced epileptic mice.
Conclusion: In the acute case of epilepsy, a compensatory mechanism of post-synaptic inhibition, possibly from ambient GABA, was observed through changes in the amplitude without significant changes in the frequency of sIPSC compared to control mice. The role of preNMDAR-mediated inhibition in epileptogenesis during the chronic condition or in the juvenile stage warrants further investigation.