Effect of Safranal on Extracellular Hippocampal Levels of Glutamate and Aspartate During Kainic Acid Treatment in Anesthetized Rats

Abstract

In this study, the effect of safranal, a constituent of Crocus sativus L., pretreatment on concomitant changes in the extracellular hippocampal levels of EAA (glutamate and aspartate) following systemic administration of KA was investigated in anesthetized rats. Safranal (72.75 mg/kg or 291 mg/kg, i. p.) was injected 40 min before KA (15 mg/kg, i. p.). A group of rats also received DZP (15 mg/kg, i. p.) 20 min prior to KA administration. The basal hippocampal concentrations of glutamate and aspartate were estimated to be 0.51 ± 0.02 μM and 0.28 ± 0.01 μM, respectively. Basal EAA levels were not affected by pretreatment with safranal. Following KA injection, there was a significant increase (p < 0.001) in the extracellular glutamate and aspartate levels (about 5-fold and 3-fold, respectively) at 80 min after injection. However, the kainite-evoked release of EAA was significantly reduced by DZP (p < 0.001) and safranal (291 mg/kg, i. p.; p < 0.001). The results of this study show that acute systemic injection of safranal reduces the extracellular concentrations of glutamate and aspartate in the rat hippocampus following KA administration.

Key words

Crocus sativus - Iridaceae - saffron - safranal - kainic acid (KA) - diazepam (DZP)

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