Abstract
Chinese herbs (CH) have been used as tradtional chinese medicine for deficiency of saliva secretion. However the mechanisms have not been clarified. This study was planned to investigate whether CH have direct effects on salivary gland or not. Submandibular gland was surgically isolated from Wistar male rat and vascularly perfused. The excretory duct was cannulated and the weight of secreted saliva was continuously recorded to calculate the fluid secretion. 20 kinds of CH were chosen, whose concentration in perfusate was prepared to be equal with the plasma concentration under clinical usage. At control, carbachol (CCh) was given at 0.2 μM. Saliva secretion formed an initial ephemeral peak at 30 s, and following gradual increase to a sustained level. By CH alone, no saliva secretion was induced by 19 kinds of CH chosen in the present experiments. However, during perfusion with 15 kinds out of 19 CH, overloading of CCh promoted the fluid secretion. The enhancement was classified to three patterns: 1) Overall sustained phase was slowly and continuously raised. 2) Sustained secretion rose continuously to reach maximum after 5-10 min, then sharply decreased to a lower sustained level than control. 3) The sustained secretion continuously increased to reach maximum after 5-10 min, then decreased slowly. Above three types of secretion were related respectively to the categories of Chinese herbs (yin-nourishing agent, qi-enhancing agent and blood activating agent). Present study introduced CH as a new tool to investigate mechanisms of fluid secretion by salivary glands. [J Physiol Sci. 2007;57 Suppl:S76]
