Effects Of Steroid On The Expressions Of Neurotransmitters In Bone Marrow Mesenchymal Stem Cells Of Rabbit

Background and Objective:The steroid-induced necrosis of femoral head cases became more and more because of the widespread using of steroid in the clinical. But the accurate etiopathogenesis of ONFH still unclear. Pervious studies showed that there is BMSCs exist in the bone marrow which could differentiate into osteoblast, adipocyte, chondroblast, or neurocyte, et al. Studies have demonstrated that steroid not only could induces the BMSCs differentiate into adipocyte, but also could effects the expressions of neurotransmitters, and then the formation and reparation of bone tissue and blood vessel are inhibited. Finally the osteonecrosis of femoral head developed. There was a report about that the expressions of neurotransmitters were effected by steroid in animal body. In this experiment, the BMSCs were isolated and cultured in vitro, the steroid was added in the culture fluid, and the effects were observed with the method of molecular biology. It's to investigate the mechanism of ONFH.Methods:The BMSCs which were distilled from the bone marrow of the limbs were isolated and cultivated by density gradient centrifugation and adherence after taking in operation. The 3rd dynasty BMSCs were divided into two groups at random. In the experimental group, the cells were treated with 10-7mol/L dexamethasone. In the control group, the cells were cultured normally. The expressions of the neurotransmitters mRNA, which were treated with or without 10-7mol/L dexamethasone on day 4,7,11,15, was investigated by the Quantitative polymerase chain reaction. In addition,the content of OC in culture fluid and the activity of ALP in cells was determined after the cells was intervened 14 days.Results:The expressions of NGFmRNA, bFGFmRNA, CGRPRmRNA, SPRmRNA and VIPRmRNA in the experimental group were lower than that in the control groups significantly, so do the content of OC and the activity of ALP, on the other hand, the expression of PPARymRNA increased drastically(P<0.01). There were no statistically differences compared among the experimental groups at different time points (P>0.05).Conclusion:High dose steriod could restrain the expressions of the neurotransmitters or their receptors which promote the process of ossification or vascularization of BMSCs, this might be one of the mechanisms in the development of steroid-induced osteonecrosis.