Characteristics Of Meridians In TCM Based On The Physiochemical Properties Of Collagen

Previous studies have shown that connective tissue is the material basis of acupuncture meridians of traditional Chinese medicine,and collagen is a major component of connective tissue.Low impedance,accumulation of reactive oxygen species(ROS),and response to Ca2+ concentration were commonly found in acupuncture meridians.Therefore,this study aims to explore the characteristics of meridians by the investigation of the effect of RJS and Ca2+ on the physiochemical properties of collagen.Three parts of experiment were carried out,first was the response of collagen to ROS.The linea alba of rat was used as a model of connective tissue to measure ROS-related indicators,and the effect of composition conditions on the properties of collagen gel was tested.On this basis,the effect of ROS on the redox potential and structure of collagen gel was analyzed.Second was the investigation of the impedance characteristics of collagen gel by AC impedance spectroscopy.Third part involved the effect of Ca2+ on the physiochemical properties of collagen.The experimental results are showed as followings:1.Results from the response of collagen to ROS showed that,1)Linea Alba,as a model tissue of acupuncture meridian,was in a high oxidative stress environment,further confirming the ROS accumulation on the meridians.2)Results from the effect of composition conditions on the redox potential and structure of collagen gels indicated that?the formation of collagen gel could decrease the redox potential.Higher concentration of collagen led to the lower redox potential and more regular of the structure.? The increment of temperature could decrease the redox potential of collagen gel and mechanical strength.At 37?,the structure was the most regular.?Increasing the pH value made the redox potential decrease.When the pH was close to the isoelectric point,the redox potential kept constant and the structure was intact.?When the buffer concentration was 75 mM,the redox potential of the collagen gel was the lowest and the structure was most regular.3)The effect of ROS on the redox potential and structure of collagen gel showed that under low H2O2 or superoxide concentrations,the gel structure was regular and the redox potential was low and the effect of ROS concentration was strong;while under high concentration of H2O2 or superoxide,the gel structure was destroyed and the redox potential increased,the effect of ROS concentration was weak.potential increased,the effect of ROS concentration was weak.2.The analysis of impedance characteristics of collagen gel suggested the concentration,temperature,pH value,buffer concentration,and ROS concentration of the collagen solution had certain correlation with the impedance value.The collagen gel was in a relative low impedance state when the concentration of collagen solution used was 11.0 mg/mL,or temperature of 45?,pH at electrically neutral,buffer concentration of 75 mM and appropriate concentrations of ROS(for example 80 ?M H2O2 or superoxide produced by Xanthine oxidase of 80-to 100-fold dilution)was set respectively.3.The effect of Ca2+ on the physiochemical properties of collagen indicated that ?the rate of collagen gel formation slowed down and the gel network structure became loosened when the Ca2+ concentration increased;?when Ca2+ concentration was in the physiological range(0.875?1.25 mM),the effect on collagen gel formation was not significant,the structure was intact,and the redox potential was low.The response of redox potential and conductivity on the change of the concentration of Ca2+ was significant;?when Ca2+ concentration was higher than the physiological concentration,the degree of cross-linking of collagen gel was extremely decreased,and the structure of collagen fiber bundles of isolated bovine tendon was destroyed,however the response of redox potential and conductivity on the change of the concentration of Ca2+ was weakened.Therefore,it was suggested that Ca2+ changed the structure mechanics of connective tissue by affecting the structure and physiochemical properties of collagen,consequently influencing the function of acupuncture meridian.All above results contributes a better explanation for the low impedance of acupuncture meridians and the concentration effects of ROS and Ca2+ by investigating the physiochemical properties of collagen,so that provides theoretical guidance for the mechanism and intervention research of acupuncture meridian.