Effect of Gosha-jinki-gan, a blended herbal medicine, on bladder activity in rats.

Purpose: We investigated the effect of the blended herbal medicine Gosha-jinki-gan on bladder activity and the autonomic nervous system in rats.

Materials And Methods: A total of 42 female rats were divided into a control diet group of 21 and a Gosha-jinki-gan diet group of 21. Rats in the control diet group were fed a standard diet, while animals in the Gosha-jinki-gan were fed a special diet containing 1.08% Gosha-jinki-gan (TJ107, Tsumura Co., Tokyo, Japan). After 4 weeks 28 rats, including 14 in the control and 14 in the Gosha-jinki-gan group, underwent continuous cystometry with physiological saline or 0.1% acetic acid solution and bladder activity was recorded. The remaining 14 rats were anesthetized with halothane, and body weight, serum amino acid (glutamate and glycine) and plasma monoamine (noradrenaline, adrenaline, dopamine and serotonin) levels were measured.

Results: The amplitude of bladder contraction on continuous cystometry with physiological saline was lower in the Gosha-jinki-gan diet group than in the control diet group, and plasma dopamine and serotonin levels were also lower in the Gosha-jinki-gan group. When cystometry was done with 0.1% acetic acid, the interval between bladder contractions was shortened in the control and Gosha-jinki-gan groups. However, the interval and duration of bladder contractions were longer in the Gosha-jinki-gan than in the control group.

Conclusions: These results suggest that Gosha-jinki-gan inhibits bladder activity by maintaining the balance of the sympathetic and parasympathetic nervous systems at a low level.