The therapeutic effect of Crocin on Scopolamine induced retrograde amnesia in male rats

Background: The cholinergic system plays an important role in learning and memory. Administration of Crocus Sativus (Saffron) or its constituent, Crocin, facilitates the formation of memory. Based on above findings, in the current study the effect of Crocin in antagonizing retrograde amnesia induced by scopolamine, a cholinergic receptor antagonist, in rats was investigated by using shuttle box apparatus.

Methods: Male Wistar rats (200 – 250 g) were tested for measuring their learning behavior in a step-through type passive avoidance task. All animals were trained by using a 1 m foot shock. The drugs were injected after the successful training. Animals were tested 24h after training to measure step-through latency (STL).

Results: Post-training injection of scopolamine (1 mg/kg) impaired memory performance on the test day. Moreover, administration of Crocin (1, 5 or 10 mg/kg) 30 min after scopolamine improved scopolamine retrograde amnesia in a dose dependent manner. On the other hand, post-training injection of Crocin (1, 5 or 10 mg/kg) had no any significant effect on passive avoidance memory by itself.

Conclusion: Considering the therapeutic effect of post-training injection of Crocin on scopolamine retrograde amnesia, it may be concluded that Crocin has an interaction with cholinergic system in formation of passive avoidance memory in male rats.