Objective To compare the effects of flap delay and vascular endothelial growth factor (VEGF) on the viability of the rat dorsal flap. Methods Thirty rats were divided into 3 groups: saline group, flap delay group and VEGF group. The rats in flap delay group underwent flap delay by keeping bipedicle untouched, and the cranial pedicle was cut 7 days later. The rats in VEGF group were given VEGF solution locally when the flaps were elevated in the operation. The ratsin saline group were given saline solution in the same way. Five days after thesingle pedicle flaps were performed, the flap survival rate was measured. Theflap tissues were collected to measure and analyze the microvascular density, diameter and sectional area by immunochemical method. Results The flap survival rate of flap delay group was similar to that of VEGF group andthere is no statistically significant difference(Pgt;0.05). The vascular diameter of flap delay group was much larger than that of saline group and VEGF group, showing statistically significant difference (Plt;0.05). The vascular density of VEGF group was much higher than that of saline group and flap delay group, showing statistically significant difference (Plt;0.05). The vascular sectional area of flap delay group was similar to that of VEGF group(Pgt;0.05). Conclusion The change in the flap after flap delayis manifested as obvious dilatation of microvessels, while the change in the flap after the injection of VEGF is manifested as obvious vascular proliferation. Both flap delay and VEGF can increase the vascular sectional area and the viability of the flap, but the mechanism is different.
Objective To study the effect of vascular endothelial cell growth factor (VEGF) on repair of bone defect with cortical bone allograft. Methods Forty five New Zealand white rabbits, weighted 2.5-3.0 kg, were made bone defect model of 1.5 cm in length in the bilateral radii and then were randomly divided into 3groups. The defect was repaired with only cortical bone allograft in the control group, with the cortical bone allograft and local injection of human recombinantVEGF in the experimental group, and with the cortical bone allograft and abdominal injection of VEGF PAb3 in the antagonist group. Roentgenography, immunohistochemical staining and tetracycline labelling were carried out to evaluate the reparative results 1, 3, 5, 8 and 16 weeks after operation. Results Immunohistochemical staining results showed that a great deal of blood vessels formed in the experimental group, and the number of blood vessels increased gradually with the time and reached the highest value at the 8th week. Tetracyclinelabelling showed the same result.The best results in callus formation, ossification rate and count of microvascular density were shown in the experimental group, while those in the control group were significantly better than those in the antagonist group (Plt;0.05),but there was no significant difference between the experimental group and the control group at the 8th week and the 16th week (Pgt;0.05). Conclusion VEGF can accelerates the bone formation and angiogenesis in the bone allografts, thus it can promote the repair of bone defects.
In order to study the effect of vascular endothelial cell growth factor (VEGF) on the survival of skin flap 30 SD rats were used. A randomized flap measuring 7.5 cm x 3.0 cm was created on the back of each SD rat. The treatment group (n = 10) received VEGF 40 ng/flap by subcutaneous injection with microinjector during and 24 hours after operation. The control groups received heparin 16 U/flap (n = 10) or normal saline 800 microliters/flap (n = 10). After operation, on the 3rd and 11th day, the survival rate of the skin flaps and the dermovascular density of each flap were investigated by histological and histo-morphometrical examination. The results showed that there was no significant difference in the survival rate between the treatment group and the controls on the 3rd day after operation, while on the 11th day, there was a significant difference between them, and the survival rate was much higher in the treatment group. Besides, dermovascular density was much more increased in the treatment group than that in the controls, especially in the distal 1/3 of the flap (P lt; 0.02). The conclusion was that VEGF could .
Objective To investigate the role of vascular endothelial growth factor-C (VEGF-C) and its receptors in the formation of lymphatic vessels and lymphatic metastasis in gastric cancer. Methods By the domestic and overseas literatures review, the expressions of VEGF-C and its receptors in gastric cancer, their role in tumor lymphatic metastasis and prospect in treatment of gastric cancer were summarized.Results There was a significant correlation between VEGF-C and its receptors and the formation of lymphatic vessels and lymphatic metastasis in gastric cancer. VEGF-C high expression might be an early event in lymphatic metastasis and could be considered as an independent predictive factor of lymphaticmicrometastasis. By inhibition of gastric cancer cell from secrete VEGF-C or blockage of the interaction of VEGF-C with VEGFR3, it was possible to inhibit tumor angiogenesis and the invasion and distant spread of cancer cells, thereby decreased mortality and improve survival. ConclusionVEGF-C and its receptors may promote the formation of lymphatic vessels and lymphatic metastasis in gastric cancer. It may be an effective way to gastric cancer for the treatments against VEGF-C and its receptors.
ObjectiveTo investigate the role of protease-activated receptor-2 (PAR-2) activation on the expression of vascular endothelial growth factor (VEGF) in MKN28 gastric cancer cells. Methods①MKN28 cells were treated with increased concentrations of trypsin (0, 0.1, 1.0, 10.0, and 100.0 nmol/L respectively) for 6 hours, or treated with 10.0 nmol/L trypsin for 3, 6, 12, and 24 hours (blank control group was treated with PBS) respectively, then the expression levels of VEGF mRNA and its protein in MKN28 cells were detected by real-time reverse transcription polymerase chain reaction (qRT-PCR) and Western bolt method, with the concentration of VEGF protein in broth was detected by enzyme linked immunosorbent assay (ELISA) method.②MKN28 cells were divided into blank control group (treated with PBS), trypsin group, trypsin+PD98059 group, trypsin+SB203580 group, PD98059 group, and SB203580 group, then the expression levels of VEGF mRNA and its protein in MKN28 cells were detected by qRT-PCR method and Western bolt method respectively. Results①The effect of different concentration of trypsin. Compared with blank control group, the expression levels of VEGF mRNA and its protein in 0.1, 1.0, 10.0, and 100.0 nmol/L group were higher (P < 0.05); compared with 0.1 nmol/L group, the expression levels of VEGF mRNA and its protein in 1.0, 10.0, and 100.0 nmol/L group were higher (P < 0.05); compared with 1.0 nmol/L group, the expression levels of VEGF mRNA and its protein in 10.0 and 100.0 nmol/L group were higher (P < 0.05); but there was no significant difference between 10.0 nmol/L and 100.0 nmol/L group (P > 0.05). The broth concentration of VEGF protein in blank control group, 0.1, 1.0, 10.0, and 100.0 nmol/L group crept upward (P < 0.05).②The effect of different treated time of 10.0 nmol/L trypsin. The expression levels of VEGF mRNA in blank control group, 3, 6, 12, and 24 hours group crept upward, and there was significant difference between any 2 groups (P < 0.05). But the expression of VEGF protein was not similar with VEGF mRNA. Compared with blank control group, the expression levels of VEGF protein in 3, 6, 12, and 24 hours group were higher (P < 0.05); compared with 3 hours group, the expression levels of VEGF protein in 6, 12, and 24 hours group were higher (P < 0.05); but there was no significant difference among 6, 12, and 24 hours group (P > 0.05). The broth concentration of VEGF protein in blank control group, 3, 6, 12, and 24 hours group crept upward, and there was significant difference between any 2 groups (P < 0.05).③The effect of extracellular regulated protein kinase (ERK) inhibitor (PD98059) and p38 inhibitor (SB203580). The expression levels of VEGF mRNA and its protein in trypsin group were all higher than corresponding indexes of blank control group, trypsin+PD98059 group, trypsin+SB203580 group, PD98059 group, and SB203580 group (P < 0.01), but there was no significant difference among blank control group, trypsin+PD98059 group, trypsin+SB203580 group, PD98059 group, and SB203580 group (P > 0.05). ConclusionActivation of PAR-2 can induce the expressions of VEGF mRNA and its protein in MKN28 gastric cancer cells, that is mediated by ERK1/2-and p38-dependent pathway.