Combined potentiating effect of byakko-ka-ninjin-to, its constituents, rhizomes of Anemarrhena asphodeloides, tomosaponin A-III, and calcium on pilocarpine-induced saliva secretion in streptozocin-diabetic mice.
The effects on pilocarpine-induced saliva secretion by a hot aqueous extract of Byakko-ka-ninjin-to (BN), its constituents, rhizomes of Anemarrhena asphodeloides, three saponins (pseudoproto-timosaponin-AIII (An-S-1), proto-timosaponin-AIII (An-S-2) and timosaponin-AIII (An-S-3)) and calcium were examined in streptozocin (STZ)-induced diabetic and normal mice. The hot aqueous extracts of BN (250 and 500 mg/kg, i.p.) and Anemarrhena (170 and 340) mg/kg, i.p.) significantly promoted salivary flow in the diabetic animals, but suppressed it in the normal controls. An-S-2 and An-S-3 but not An-S-1 (10 mg/kg, i.p.), significantly promoted salivary How in the diabetic animals. The potency order was An-S-3 >> An-S-2 >> extract. The hot aqueous extracts of BN and Anemarrhena increased the protein content of saliva in a dose-dependent manner. Combination of An-S-3 (0.1 mg/kg, i.p.) with CaCl2 (2 and 4 mg/kg, i.p.) potentiated salivary flow compared with the respective effect of each on its own. These results demonstrated that 1) An-S-3 was mainly responsible for saliva secretion of the hot aqueous extract, and 2) the effect of An-S-3 was potentiated by combination with calcium, suggesting combined effects of Byakko-ka-ninjin-to containing Anemarrhena asphodeloides and gypsum fiber (calcium).