紫杉醇对兔血管内皮和平滑肌细胞增生影响的差异及意义

目的探讨紫杉醇对兔血管内皮和平滑肌增生影响的差异及意义.方法将兔血管平滑肌细胞接种于共培养体系上室、内皮细胞接种于下室建立体外内膜修复模型,观察紫杉醇对兔血管平滑肌和内皮细胞3H-TdR掺入、细胞计数和迁移率的影响,用直线回归法计算紫杉醇对平滑肌和内皮细胞增生迁移的半数有效抑制浓度IC50.结果在1 nmol·L-1～1 μmol·L-1之间,紫杉醇呈浓度依赖地抑制平滑肌细胞3H-TdR掺入、细胞计数和迁移(n=6, P＜0.01).在10 nmol·L-1～1 μmol·L-1之间,紫杉醇呈浓度依赖地抑制内皮细胞3H-TdR掺入、细胞计数和迁移(n=6, P＜0.01).1 nmol·L-1紫杉醇对内皮细胞3H-TdR掺入和细胞计数有抑制倾向,但与对照组相比无统计学差异.而1 nmol·L-1的紫杉醇却已显著抑制内皮细胞迁移(n=6, P＜0.01).紫杉醇对兔血管平滑肌细胞增生、迁移抑制的IC50分别为 10.09±0.47、9.16±0.54 nmol·L-1,对内皮细胞增生、迁移抑制的IC50分别为 19.05±0.35、5.37±0.51 nmol·L-1.10 nmol·L-1紫杉醇作用 20 min 在观察时间内能持续抑制融合内皮组平滑肌增生,而对数内皮组平滑肌增殖在10 d时明显高于对照组.结论紫杉醇在抑制兔血管平滑肌细胞增生的同时也抑制内皮增生,紫杉醇干预后平滑肌细胞增生延迟与内皮细胞再生延迟密切相关.

Different growth response of rabbit's vascular endothelial and smooth muscle cells to Paclitaxel

AIM: To investigate the effect of paclitaxel on the quantitative growth of rabbit's vascular smooth muscle cells (SMCs) and endothelial cells (ECs) and their relationship in vitro. METHODS: An ex vivo model of endothelium repair was developed in which rabbit's SMCs were inoculated in the upper chamber and rabbit's ECs in the lower chamber of a co-culture system. 3 H-TdR incorporation and cell counting were used to determine the effect of paclitaxel on the quantitative proliferation of rabbit's vascular ECs and SMCs. The migration rate was analyzed to determine the effect of paclitaxel on the migration of rabbit's vascular ECs and SMCs. The IC50 of paclitaxel on ECs and SMCs was calculated. RESULTS: The 3 H-TdR incorporation, cell counting and migration of rabbit's vascular SMCs were inhibited by paclitaxel of 1 nmol·L-1-1 μmol·L-1 in a concentration-dependent manner (n=6, P<0.01). The 3 H-TdR incorporation and cell counting of rabbit's vascular ECs were inhibited by paclitaxel of 10 nmol·L-1-1 μmol·L-1 and migration by paclitaxel of 1 nmol·L-1-1 μmol·L-1 in a concentration-dependent manner (n=6, P<0.01). The 3 H-TdR incorporation assay resulted in the IC50 of 10.09±0.47 nmol·L-1 on SMCs and 19.06±0.35 nmol·L-1 on ECs proliferation. The migration assay resulted in the IC50 of 9.16±0.54 nmol·L-1 on SMCs and 5.37±0.51 nmol·L-1 on ECs migration. Paclitaxel (10 nmol·L-1, 20 min) inhibited SMCs growth of the confluent ECs group during the observed period. However, increased SMCs growth was observed in the proliferative ECs group 10 days after paclitaxel intervention. CONCLUSION: Paclitaxel inhibits not only SMCs but also ECs growth in rabbit's vascular. The delayed SMCs proliferation is closely related with the delayed ECs regeneration induced by paclitaxel.