Intake of fermented soybean (Natto) increased locomotor activity in mice

Abstract

We fed mice food granules containing fermented soybean (natto in Japanese) powder (hereafter "natto granules") for 14 d to investigate whether natto granules had any effects on mouse behavior. We noted an enhancement of locomotor activity in natto-granule-fed mice compared to control and soybean-pellet-fed mice. This enhanced locomotor activity was blocked by a low dose of haloperidol (1 μg/kg i.p.), a dopamine receptor antagonist, but not by methysergide, a serotonin 5-HT1/2 receptor antagonist. The results suggest that the enhanced locomotor activity induced by continuous intake of natto granules in mice is sensitive to haloperidol. © 2007 Pharmaceutical Society of Japan.