Effect of Zena F-III (R), a liquid nutritive and tonic drug, on the neurochemical changes elicited by physical fatigue in mice

The effects of a liquid nutritive and tonic drug (NTD) on the neurochemical changes elicited by physical fatigue in mice were investigated in terms of the calcium-dependent dopamine synthesizing function of the brain. In this study, Zena F-III(R) (Taisho Pharmaceutical Co., Ltd., Japan), one of the most popular NTDs in Japan, containing 15 crude drug extracts together with taurine, caffeine, and vitamins, and formulated based on the precepts of t raditional Chinese medicine, was used. Male mice were forced to walk for 0- 6 h at a speed of 3 m/min using a programmed motor-driven wheel cage. The s erum and brain calcium levels in the mice were significantly increased foll owing forced walking. The increase in brain calcium level began later and w as more gradual than that in the serum calcium level, and reached its maxim um value following forced walking for 3 h. The neostriatal dopamine level w as also significantly increased, and locomotor activity significantly decre ased following forced walking for 3 h. Prior oral administration of F-III ( 10 ml/kg) attenuated the increases in the serum and brain calcium levels, t he increase in the brain dopamine levels, and the decrease in locomotor act ivity induced by forced walking. Taking into consideration these findings w ith our previous reports, it is suggested that physical fatigue leads to an increase in dopamine synthesis in the brain through a calcium/calmodulin-d ependent system, thereby inducing behavioral changes, and that F-III inhibi ts this pathway and may alleviate overwork-induced physical fatigue. (C) 20 00 Elsevier Science Inc.