Abstract:

The effects of L-theanine on barbiturate-induced sleeping time, subthreshold barbiturate-induced sleeping time and barbiturate-induced sleeping latency period in mice were investigate. Healthy ICR mice were randomly divided into four groups of 12 mice each: control group fed with distilled water and three treatment groups fed L-theanine at low-, medium-, and highdoses of 50,100 and 200 mg/(kg bw·d). for 30 days. L-Theanine was able to improve sleep function of mice to a certain extent and the best effect was found in the medium-dose-treated mice. However, no direct hypnotic effect of L-theanine was observed while it was able to prolong the sleeping time induced by pentobarbital sodium [that of the medium-dose-treated mice reached (40.3 ± 26.0) min] and to enhance the sleeping rate induced by barbital sodium at the threshold dose (that of the medium-dosetreated mice reached 33.3%). L-Theanine also could significantly decrease (P ＜ 0.05) the sleeping latency period induced by barbital sodium [that of the medium-dose-treated mice reached (30.32 ± 4.8) min].

Key words: L-theanine, mice, sleep improvement