Expression Of NGF, TrkA And P75 ^NTR In Ischemic Muscles Of Mice And Their Interactions

Objective:To measure quantitative changes in messenger RNA (mRNA) expression levels of NGF、p75NTR and Trk A in ischemic rat’s skeleton muscle and discuss the relationship among the tree genes in process of angiogenesis and innervation under ischemic condition.Method:To establish rat models of ischemia, denervation, ischemia together with denervation. This study analyzes alterations in the mRNA levels of the mentioned genes at3days,7days and14days after establishment of the rat models using real-time polymerase chain reaction. HE staining and PCNA immunohistochemistry were used to analyze pathological changes and proliferation status of the muscles.Results:over expression of NGF mRNA in three groups were observed. In ischemia group, positive correlation was showed between the trends of P75NTR and Trk A mRNA alteration. In denervation group, negative correlation was showed between the mRNA alterations of mentioned genes. There was no correlation between the mRNA alterations of two mentioned genes in ischemia together with denervation group. Vascular endothelia cells were hyper-proliferated at3days after operations in the three groups. Proliferation level of vascular endothelia cells was the lowest in denervation group and the highest in ischemia together with denervation group.Conclusion:Under ischemia condition, P75TR helps modulate the affinity between Trk A and NGF and accelerate the regeneration and recovery of vascular and nerves; under denervation condition, P75NTR binds with NGF to activate apoptosis of nerves, and expression of Trk A mRNA is inhibited in some degree.