Objective To study the effects of vitamin E on the proliferation and collagen synthesis of rat hepatic stellate cells treated with interleukin-2 (IL-2 ) or tumor necrosis factor-α (TNF-α).Methods Hepatic stellate cells were isolated from male Sprague-Dawley rats by using modified Friedman’s method. Using the isolated cells cultured and treated with IL-2 or TNF-α, we studied the effects of vitamin E on their proliferation and collagen synthesis through an 3H-thymidine and 3H-proline incorporation assay, as well as through observation of these cells under a contrary phase microscope. Results Adding IL-2 increased the both proliferation and collagen synthesis of hepatic stellate cells. Their proliferation was also increased by the addition of TNF-α, although it decreased collagen synthesis. Vitamin E had marked inhibitory effects on the ability of cells treated with IL-2 or TNF-α to reproduce or synthesize collagen. Conclusion Vitamin E can inhibit the proliferation and collagen synthesis of hepatic stellate cells. It is possible that vitamin E affects liver fibrosis through these activities. Objective To study the effects of vitamin E on the proliferation and collagen synthesis of rat hepatic stellate cells treated with interleukin-2 (IL-2) or tumor necrosis factor-α (TNF-α). Methods Hepatic stellate cells were isolated from male Sprague -Wawley rats by using modified Friedman’s method. Using the isolated cells cultured and treated with IL-2 or TNF-α, we studied the effects of vitamin E on their proliferation and collagen synthesis through an 3H-thymidine and 3H-proline incorporation assay, As well as through observation of these cells under a contrary phase microscope. Results 增加 IL-2 increased the both proliferation and collagen synthesis of hepatic stellate cells. Their proliferation was also increased by the addition of TNF-alpha, although it decreased collagen synthesis. Vitamin E had marked inhibitory effects on the ability of cells treated with IL-2 or TNF-α to reproduce or synthesize collagen. Conclusion Vitamin E can inhibit the proliferation and colla gen synthesis of hepatic stellate cells. It is possible that vitamin E affects liver fibrosis through these activities.