目的 探讨大鼠下腔静脉间充质干细胞（IVC-MSCs）的原代培养、传代扩增及鉴定方法，为MSCs提供更多新型来源。方法 采用“机械碎化联合酶解法”分离大鼠IVC-MSCs，通过形态学观察，细胞表面免疫标志物及成骨/成脂/成软骨三系分化潜能检测，多维度、多层次对IVC-MSCs生物学表征进行鉴定。结果 从大鼠下腔静脉中分离的原代细胞呈短梭形，贴壁生长，增殖活力强，传代至第4代细胞，流式细胞术检测：高表达CD90 （97.57 ± 2.83）%、CD73 （99.67 ± 0.06）%、CD44 （99.53 ± 0.06）%，MSCs标志物阳性率均>95%；同时低表达CD45 （3.24 ± 0.19）%、CD34 （3.82 ± 0.31）%、CD11b/c （4.88 ± 0.24）%，造血干细胞及单核巨噬细胞系阳性率均<5%，符合MSCs的免疫表型特征。传代细胞经特定培养液诱导后，可分化为相应的成骨细胞、脂肪细胞及软骨细胞，具备多向分化潜能。结论 成功建立了大鼠IVC-MSCs培养体系，将MSCs的“种子库”拓展至下腔静脉这一少见来源，拓宽了MSCs的获取途径，为后续解析其生物学特征，阐明静脉血管稳态调控机制及开展血管性疾病的干细胞治疗奠定了可重复、可推广的技术平台，亦为稀有组织来源的干细胞临床转化研究提供了更多范式。

Objective To establish primary culture，expansion，and identification methods for rat inferior vena cava (IVC)-derived mesenechymal stem cells(MSCs)，providing a novel alternative source. Methods Rat IVC-MSCs were isolated using mechanical fragmentation combined with enzymatic digestion. Multidimensional characterization included morphological observation，flow cytometry for surface immunophenotyping，and trilineage differentiation (osteogenic，adipogenic and chondrogenic) induction with histological staining. Results Primary cells exhibited short spindle morphology with adherent growth and robust proliferation. At passage 4，marker protein expression: CD90 （97.57 ± 2.83）%、CD73 （99.67 ± 0.06）%、CD44 （99.53 ± 0.06）%，positive rate of positive markers > 95%；CD45 （3.24 ± 0.19）%、CD34 （3.82 ± 0.31）%、CD11b/c （4.88 ± 0.24）%，positive rate of negative markers <5%. Induced cells successfully differentiated into osteoblasts，adipocytes，and chondrocytes，demonstrating multipotency. Conclusion We successfully established a rat IVC-MSC culture system，expanding the MSC“seed bank” to this uncommon source. This broadens MSC acquisition avenues and establishes a reproducible platform for investigating biological characteristics, elucidating venous homeostasis mechanisms, and developing stem cell therapies for vascular diseases，providing a paradigm for clinical translation of stem cells from rare tissue sources.