To establish a murine carotid artery transplantation model for the study of the chronic rejection, 80 rats were divided into two groups, an allotransplant （ACI-Lewis） group and an isotransplant （Lewis-Lewis） group （control group）. The donor carotid artery and the recipient carotid artery were anastomosed by using a polyethylene cuff （internal diameter： 0.7 mm, length： 3 mm）.The pathological changes of carotid artery transplant were observed 14, 28 and 56 days after the transplantation. The results showed that the model was successfully established in 95% of the animals. The chronic rejection-associated arteriosclerosis was induced 28 days after the transplantation. The new chronic rejection model of carotid artery by using cuff technique caused fewer traumas and was easy to make. The pathological changes of the transplant mimicked the chronic rejection-associated arteriosclerosis found in human transplant.
The inhibitory effect of astilbin on transplant arteriosclerosis in murine model of thoracic aorta transplantation was examined. Model of rat thoracic aorta transplantation was established. Ninety rats were divided into three groups. In isograft group, the thoracic aorta of Brown Norway （BN） rat was anastomosed with the abdominal aorta of another BN rat. In allograft group, the thoracic aorta of BN rat was anastomosed with the abdominal aorta of Lewis rat. In astilbin group, the rats receiving allo-transplantation were given astilbin 5 mg/kg per day for a time of 28 days. The donor thoracic aorta and the recipient abdominal aorta were anastomosed by means of a polyethylene can- nula （inner diameter： 1.5 mm, length： 3 mm length）. The grafts were histologically examined for structural changes. The areas of arterial lumen and endatrium were calculated. Our results showed that, in the allograft group, 28 days after allografting, conspicuous proliferation of smooth muscles and infiltration with a great number of inflammatory cells were found in the tunica intima and tunica media. Astilbin significantly inhibited the proliferation of smooth muscles and ameliorated the infiltration of inflammatory cells thereyby prevent against the development of transplant arteriosclerosis. It is concluded that asltilbin can effectively prevent the development of arteriosclerosis in allotransplant by inhibiting the proliferation of smooth muscles and inhibit the proliferation of smooth muscles in tunica of intima and media and reducing infiltration of the inflammatory cells.
This study examined the effect of astilbin on the proliferation of rat aortic smooth muscle cells (RASMCs) induced by angiotensin Ⅱ (AngⅡ) and explored the possible mechanisms. Cell proliferation model of RASMCs was induced by treatmente with AngⅡ. Cells were randomly divided to 8 groups. Normally cultured VSMCs serves as blank control group; in AngⅡ model group, cells were treated with AngⅡ at 10–7 mol/L; in three astilbin groups, cells were treated with 10, 15, 30 mg/L of astilbin; in three AngⅡ+astilbin groups, cells were treated with AngⅡ (at 10–7 mol/L) and astilbin at 10, 15, 30 mg/L. Cell proliferation ability was detected by MTT method and the cell cycles and proliferation index were flow cytometrically determined. The expression of c-myc mRNA was assessed by using reverse transcription polymerase chain reaction (RT-PCR), and the expression of NF-κB in RASMCs was immunocytochemically observed. Our results showed that MTT metabo-lism in RASMCs in the basic and AngII stimulated situation was inhibited by astilbin, and the cells numbers of G0/G1 phase were increased and that of G2/S phase were decreased markedly. Not only highly expression of c-myc gene stimulated by AngⅡ could be inhibited by Astilbin significantly, but also the expression of NF-κB protein can be down regulated by Astilbin. We are led to conclude that astilbin astilbin can inhibit the AngⅡ-mediated proliferation of RASMCs by blocking the transition of RASMCs from G0/G1 phase to S phase and by down-regulating the expression of NF-κB, c-myc gene.
