Experimental Study On The Effects Of Tongxinluo Capsule On Relaxin And Its Receptors In Rats With Myocardial Fibrosis Induced By Isoproterenol

ObjectiveThe aim of the study was observed the effection of Tongxinluo capsule in Isopropyl induced Myocardial Fibrosis rats of endogenous Relaxin and its receptor. To explore the mechanisms of Tongxinluo capsule on restraining Myocardial Fibrosis.MethodsFed the 50 SD rats 7 days in older to adapt the laboratory environment,and then divided into 5 groups randomly,each groups contain 5 female rats and 5 male.They were normal group, model group, captopril tablets respectively in the control group (for short as the control group), Tongxinluo capsule high-dose group(the high dose group), Tongxinluo capsule low-dose group (the low dose group).Except the normal group, the rest rats of the groups injection in back subcutaneous of ISO 5mg/kg/day for seven days to copy the model of myocardial fibrosis rat.At the same time, give Tongxinluo capsule and captopril pull to treatment 21d.On the experiment 29 day, measured weight in rats,collected the blood about 4ml from heart and then take out the heart, flushing with ice saline.Filter paper dips in dry, measured the heart weight. All the heart cut into two pieces for pathological and detection.Used ELISA method to measure the rats serum relaxin and its receptor levels. Observed the change of myocardial collagen by HE and MASSON staining.Using SPSS 19.0 statistics software to analysis and inference. Comparison between groups using single factor analysis of variance or nonparametric test. Two related variables analysis by using Pearson. P<0.05 was statistically significant.Results1.Animal model analysis:The ISO injected in back subcutaneous to copy the model of myocardial fibrosis rats was safety and feasible.2.The rats weight:Compared with the model group(283.27±32.41g),the weight of control group weight (298.89±43.53g) and Tongxinluo each dose group (307.81±54.80g,318.98±50.31g) was significantly higher (P<0.05). At the same time the weight of the high dose group was higher than the low dose group(P<0.05).3.The weight of the rat heart and heart weight index:The heart weight of model group was the heaviest and normal group was the lightest, there was difference between them(P<0.05). But in treatment groups, each dose group of Tongxinluo was no significant difference compared with control group(P> 0.05). The heaviest of heart weight index was model group(5.81 ± 0.43), the lightest was blank group (3.88±0.18). The HWI of Tongxinluo high dose group was lower than the control group and Tongxinluo low dose group(P<0.05).4.Myocardial collagen volume fraction (CVF):The CVF of normal group rats was the lowest (4.17±0.25), and model group was the highest (37.48 ±3.48%)(P<0.01). In the drug intervention group, there was no significant difference between the high dose group (28.35 ±1.70%) and the control group (26.86±3.05%), but compared with the low dose group (32.41±1.95%),they were lower (P<0.05).5.The Relaxin:The highest levels of Relax was model group (395.63±31.31 pg/ml) and the lowest was normal group(131.61±27.14pg/ml),but in treatment groups,the high dose group and the low dose group were higher than the control group(P<0.05).6.Relaxin receptor levels in the myocardial:The highest Relaxin receptor was normal group and the lowest was model group.After treatment there was no significant difference between control group and Tongxinluo each dose groups (P> 0.05).7.Correlation analysis:In this experiment, we found that Relaxin lever and its receptor content show significant linear positive correlation in normal group (P< 0.05).But in MF,they were negativity correlation. But the specific relevant degree of relatively still needed further research and exploration.8.Sex difference analysis:We had not observed the differences of Relaxin and its receptor between the male and female in each group in the experiment.Conclusion1.The ISO can successfully manufacturing myocardial fibrosis model in the rat.2. In the experiment,we found that Tongxinluo capsule can improve the overall situation to the rat of myocardial fibrosis caused by isopropyl. It can prevent myocardial fibrosis,this function was closely related to the dose of Tongxinluo.The mechanism of prevent MF might be related to regulating relaxin and its receptor level for rats.3.Relaxin levels and its receptor expression had nothing to do with gender of rats in this experiment.