[ effect of chronic oral feeding of Apium graveolens on learning and memory in diabetic rats]

ABSTRACT

Diabetes mellitus [especially type I] is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Considering the beneficial effect of Apium graveolens [AG] on lipid peroxidation in hyperlipidemia and on serum lipids in diabetes mellitus, this research study was conducted to evaluate the effect of chronic oral administration of AG on learning and memory in diabetic rats using passive avoidance test. For this purpose, male Wistar diabetic rats were randomly divided into control, AG-treated control, diabetic, and AG-treated diabetic groups. AG treatment [at a weight ratio of 1/15 mixed with rat chow] continued for 6 weeks. For induction of diabetes, streptozotocin was injected i.p. at a single dose of 60 mg/kg. For evaluation of learning and memory, initial latency [IL] and step-through latency [STL] were determined at the end of study using passive avoidance test. Meanwhile, alternation behavior percentage was determined using Y maze. There was a significant increase [p<0.05] in IL in diabetic and AG-treated diabetic groups after 6 weeks as compared to control group. In this respect, there was no significant difference between diabetic and AG-treated diabetic groups. On the other hand, STL significantly decreased [p<0.05] in diabetic group and significantly increased [p<0.05] in AG-treated diabetic group as compared to control group at the end of study. In addition, STL did not significantly change in AG-treated control group in comparison with control group. Results of Y-maze showed that alternation was significantly higher [p<0.05] in AG-treated diabetic rats relative to untreated diabetic ones and AG treatment did not have any significant effect in control group. Chronic oral administration of AG could enhance the consolidation and recall capability of stored information and improve spatial memory in diabetic animals