OBJECTIVETo study the action characteristics of "two-way application and conditioned dominance" of traditional Chinese medicines with neutral property by observing the action characteristic of 10 traditional Chinese medicines capable of promoting blood circulation and removing blood stasis with neutral property in the microcirculation in rats with heat stagnation and blood stasis syndrome.

METHODThe rat model with heat stagnation and blood stasis syndrome was established by injecting carrageenan and dry yeast, and the rat model with cold stagnation and blood stasis syndrome was built by the body freezing method. Ten traditional Chinese medicines with neutral property, including 5 with hot property and 5 with cold property, were selected for intervention to observe blood flow rate and flow state indicators in rat auricles and make a comparative analysis on action characteristics of traditional Chinese medicines with neutral property.

RESULTANOVA showed that among the 10 traditional Chinese medicines with neutral property, 6 such as Typhae Pollen, Sappan Lignum and Vaccariae Semen can obviously increase the blood flow rate (P < 0.01 or P < 0.05) in the above two models; all of the 5 traditional Chinese medicines with cold property can increase the blood flow rate (P < 0.01 or P < 0.05) in the rat model with heat stagnation and blood stasis syndrome, but only Salvia miltiorrhiza can increase the blood flow rate (P < 0.01 or P < 0.05) in the rat models with cold stagnation and blood stasis syndrome, while other medicines showed no notable effect; among the 5 traditional Chinese medicines with hot property, Carthamus tinctorius and Ligusticum chuanxiong can increase the blood flow rate (P < 0.01 or P < 0.05) in the rat models with cold stagnation and blood stasis syndrome, but had no obvious effect to the blood flow rate in the rat models with heat stagnation and blood stasis syndrome. According to the analysis on average blood flow rate, traditional Chinese medicines with natural and cold properties showed similar effect on heat stagnation and blood stasis syndrome and better effect in increasing blood flow rate than those with hot property; those with natural and hot properties showed similar effect and better effect in increasing blood flow rate than those with cold property.

CONCLUSIONUnder the condition of heat stagnation and blood stasis syndrome, traditional Chinese medicines with neutral property have the similar action characteristics with those with cold property; wile under the condition of cold stagnation and blood stasis syndrome, traditional Chinese medicines with neutral property have the similar action characteristics with the Chinese medicinal herbs with hot property. This indicates the action characteristics of "two-way application and conditioned dominance" of traditional Chinese medicines with neutral property to some extent.