Effect of tarragon (Artemisia dracunculus L.) extract on spatial memory in rats exposed to chronic restraint stress

Tarragon (Artemisia dracunculus L.) has antioxidant, anti-inflammatory and analgesic effects. The objective of this study was to investigate the effect of Tarragon alcoholic extract on spatial learning and memory deficits, induced by chronic immobilization stress in male rats.

In this experimental study, 60 male Wistar rats were divided into 6 groups (each group of 10 rats): Control(without treatment), under stress, receiving 100 mg / kg Tarragon extract, receiving 500 mg / kg Tarragon extract, Stress receiving and 100 mg / kg Tarragon extract simultaneously, and  finally Stress receiving group and 500 mg / kg tarragon extract simultaneously. The rats in under stress group, 6 hours every day for 21 consecutive days they encountered with immobilized stress. Groups receiving Tarragon extract, during this period, the doses of 100 mg / kg.bw and 500 mg / kg.bw were extracted by gavage, and two groups receiving the extract and stress simultaneously, in addition to receiving Tarragon extract at the same doses they also faced stress. Spatial learning and memory of animals were evaluated by using the Morris water maze test.

Immobilized stress impaired learning and memory in animals. Delay time (seconds) and distance (cm) moved to reach the hidden platform was significantly increased in the stress group compared to the control group (P <0.01 and P <0.05, respectively). Also in probe test, total elapsed time (s) and distance (cm) in target quadrant decreased significantly in stress group compare with control group (p<0.001 and p<0.05 respectively). Receiving both doses of Tarragon extract improved spatial learning and memory in under stressed rats.

The results of this study indicate that Tarragon extracts prevent memory impairment and may be useful in preventing and treating of neuro-degenerative diseases due to stress.