IMPACTS ON THE EXPRESSION OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN ISCHEMIC BRAIN TISSUE TREATED WITH CLUSTER PUNC-TURE ON SCALP ACUPOINTS IN RATS

Objective To probe into the impacts on the expression of vascular endothelial growth factor （VEGF） in ischemic brain tissue treated with cluster puncture on scalp acupoints in rats, Methods 128 rats were randomized into pseudo-operation group, model group, scalp-needling group and cluster-needling group, In scalp-needling group, penetration method was used on the focal side from Bǎihuì （百会 GV20） to Qǔbīn （曲鬓 GB7）, and in cluster-needling group, penetration method was used on both sides from GV20 to GB7, and a common needling on GV 20. Needles were punctured 2 mm in depth, constantly rotated for 10min, retained for 2 h. Immunohistrochemical method was applied to determine VEGF expression and microvessel density （MVD）. Results With the intervention of cluster puncture on scalp acupoints, VEGF： expressions on every time-spot after ischemia were enhanced apparently, superior to those in scalp-needling group. On the three time-spots of the 7^th, 14^th and 21^st days, MVD was increased after cluster puncture on scale acupoints, superior to those in scalp-needling group. Conclusion Cluster puncture on scalp acupoints up-regulated VEGF expression and promoted regeneration of microvessel.

Isoflurane induces expression of vascular endothelial growth factor through activating protein kinase C in myocardial cells

Objective： Vascular endothelial growth factor （VEGF） plays important roles in establishing collateral circulation of ischemic myocardium. This study aimed to investigate the effect of isoflurane on VEGF expression and the potential intracellular signal transduction pathway in cultured rat myocardial cells in order to further reveal the molecular mechanism of myocardial preservation of isoflurane. Methods： Primary myocardial cells of Sprague-Dawley rats were isolated and cultured. They were divided randomly into control group, isoflurane group, protein kinase C （PKC） inhibitor group and PKC inhibitor＋isoflurane group where cells were respectively incubated without any treatment, treated by 0.5, 1.0 and 1.5 minimum alveolar concentration （MAC） of isoflurane for 6 hours, by PKC inhibitor calphostin C at a final concentration of 50 nmol/L and by 50 nmol/L calphosfin C＋ 1.0 MAC isoflurane for 6 hours. VEGF expression was detected by enzyme-linked immunosorbent assay （ELISA） and the expression levels of PKC isoforms were determined by Western immunoblotting method. Results： Isoflurane increased the VEGF expression in myocardial cells in a dose-dependent way. VEGF levels were significantly higher in 1.0 and 1.5 MAC isoflurane groups than in the control group （both P〈0.01）. The effect of isoflurane on upregulating VEGF expression was blocked by PKC inhibitor calphostin C （P〈0.01）, but calphostin C did not alter VEGF expression （P〉0.05）. Isoflurane induced the activation and translocation of PKC Immunoblotting analysis revealed that the immunoreactivity of PKC ε increased significantly in the membrane fractions and deceased significantly in the kytoplasm fractions for cells treated with 1.0 MAC isoflurane as compared with the untreated cells, but not of PKC a, PKCα and PKCζ （P〈0.01）. Conclusion： Isoflurane induces myocardial cells to release VEGF through activating PKCε from the endochylema to the cytomembrane, suggesting a possible novel mechanism of isoflurane protecting myocardial cells.