Mechanism of local time-sensitive stimulation effect of catgut and polyglycolide-co-lactide thread embedding at"Zusanli"acupoint area of rats / 中国组织工程研究

ABSTRACT

BACKGROUND:The researchers noted that upon embedding clinical-grade catgut and polyglycolide-co-lactide threads in the normal human"Zusanli"(ST 36)acupoint,the local area displayed temporal and inflammatory stimulatory effects,resulting in thread differentiation.However,the underlying mechanism behind thread involvement remains to be studied. OBJECTIVE:To investigate the expression levels of calcitonin gene-related peptide,5-hydroxytryptamine,leukotriene B4,and bradykinin at point"Zusanli"(ST 36)in rats after embedding catgut and polyglycolide-co-lactide respectively at different time points. METHODS:110 male SD rats were divided into a blank group(10 rats),a catgut embedding group(50 rats),and a polyglycolide-co-lactide embedding group(50 rats)according to the random number table method.In the blank group,no thread was embedded.In catgut embedding group and the polyglycolide-co-lactide embedding group,the thread was embedded in the left side of the ST36 acupoint once.Tissue was collected from the left side of the ST36 acupoint area 8 hours,3,7,14,and 21 days after embedding.The expression levels of calcitonin gene-related peptide and 5-hydroxytryptamine were detected by immunohistochemistry,and the contents of leukotriene B4 and bradykinin were detected by ELISA. RESULTS AND CONCLUSION:(1)Compared with the blank group,the expression of calcitonin gene-related peptide,5-hydroxytryptamine,bradykinin,and leukotriene B4 was significantly increased in the 8 hours,3,7,14,and 21 days of the catgut embedding group(P<0.05);calcitonin gene-related peptide expression was significantly increased in 8 hours,3,7,and 14 days in the polyglycolide-co-lactide embedding group(P<0.05);the expression of bradykinin was significantly increased in 8 hours,3,and 7 days(P<0.05);the expression of leukotriene B4 was significantly increased at 8 hours,3,7,14,and 21 days(P<0.05).(2)Compared with the polyglycolide-co-lactide embedding group,the expression of calcitonin gene-related peptide was increased at 7,14,21 days after thread embedding(P<0.05),and the expression of 5-hydroxytryptamine was increased at 8 hours,3,7,14 and 21 days after thread embedding(P<0.05);contents of leukotriene B4 and bradykinin in tissues were increased at 8 hours,3,14 and 21 days after embedding(P<0.05)in the catgut embedding group.(3)The results show that calcitonin gene-related peptide,5-hydroxytryptamine,leukotriene B4,and bradykinin in the acupoint region alter after catgut embedding in the ST36 of rats,as well as the alteration of calcitonin gene-related peptide,leukotriene B4,and bradykinin is found in the acupoint region after polyglycolide-co-lactide embedding in rats,which may be one of the mechanisms involved in the local time sensitive stimulus effects caused by embedding threads at acupoints.Moreover,there is a discernible difference between the two thread types.