The Protective Effects of Crocin on Input-Output Functions and Long-term Potentiation of Hippocampal CA1 Area in Rats Exposed to Chronic Social Isolated Stress.

The lack of social communication (isolation stress) is associated with the primary risk of brain functions. On the other hand, crocin as one of effective components of saffron is helpful for improvement of memory. Therefore, the protective effect of two doses of crocin on cellular mechanism of memory in rats exposed to chronic social isolated stress was investigated in present study. Chronic isolation stress (CIS) was induced 6h/day, and crocin was administrated for a period of 21 days at two doses of 30 and 60 mg/kg. The electrophysiological and cellular mechanism of memory in the CA1 area of the hippocampus were investigated. Also, the corticosterone and glucose levels were assayed in the hippocampus and frontal cortex. It was concluded that the chronic isolation stress impaired neural excitability and long-term plasticity in the CA1 area due to elevated corticosterone in the hippocampus and probably the frontal cortex. The low and high doses of crocin improved excitability and long-term plasticity in the chronic isolation stress group by only decreasing corticosterone levels in the hippocampus, but not the frontal cortex. Also, the corticosterone levels significantly increased in the frontal cortex and especially the hippocampus. Also, the glucose levels did not change in the hippocampus and frontal cortex in all experimental groups.