Purpose: To investigate the expression and relationship of substance P(SP) and vascular endothelial growth factor (VEGF) in human dental pulp under the normal and pathological conditions, so as to study their role in pulp microcirculation. METHONDS: Ten teeth extracted for orthodontic or impacted reason were chosen as normal group. Twenty-nine traumatic teeth from the same age group needing root canal therapy were divided to initial-stage trauma group, early-stage inflammation group, later-stage inflammation group. Immunohistochemical technique was applied to determine the expression and distribution of SP and VEGF in each group. The data was analyzed by one-way ANOVA and correlation analysis with SPSS13.0 software package.
Results: Compared with normal group,SP expression in other groups was significantly down-regulated(P<0.05). The VEGF expression in early-stage inflammation group was significantly up-regulated compared with the other groups (P<0.05), but down-regulated in later-stage inflammation group (P<0.05). The expression of SP and VEGF had negative correlation in different groups(r=-0.378,P<0.05).
Conclusions: SP may induce the pulp microcirculation change by regulating VEGF, and participate in pulp neurogenic inflammation.