摘要
糖皮质激素对人原始巨核白血病细胞系（ＨＩＭｅｇ）的增殖分化过程有调节作用，且由糖皮质激素受体（ＧＲ）介导。用放射配体结合分析法及分子杂交进一步研究了视黄酸对ＨＩＭｅｇ细胞ＧＲ的表达调节作用。结果表明，视黄酸可使ＧＲ结合活性明显提高，且具有时间依赖性，２４ｈ后约提高２倍：以［３２Ｐ］标记的ＧＲｃＤＮＡ片段为探针，用ｄｏｔｂｌｏｔ杂交分析表明，视黄酸亦可使ＧＲｍＲＮＡ水平升高，表明视黄酸对ＧＲ结合活性的影响至少部分地发生于ｍＲＮＡ水平。为进一步阐明视黄酸对ＧＲ调节的可能意义，还观察了糖皮质激素与视黄酸联合应用对ＨＩＭｅｇ细胞增殖过程的影响，发现二者具有相加作用，提示视黄酸对ＧＲ的调节作用具有生物学意义。
Our recent studies showed that glucocorticoids play an important role in the processes responsible for proliferation and differentiation of a human megakaryoblastic leukemia cell line (HIMeg) and that the effects of glucocorticoids are mediated by glucocorticoid receptor(GR) in these cells.The regulation of GR expression in HIMeg cells by retinoic acid was further studied utilizing radioligand binding assay and molecular hybridization analysis.It was shown that retinoic acid could significantly increase the GR binding activities in a time-dependent manner,reaching a maximum of about 2-fold 24h following treatment.Dot blot hybridization analysis utilizing 32P-labeled GR cDNA fragment as a probe showed that GR mRNA was also up-regulated by retinoic acid,suggesting that the regulating effects of retinoic acid on GR occurred at least partially at GR mRNA levels. To explore further the possible consequence of retinoic acid-induced regulation of GR exp ression in HIMeg cells,the combined effects of glucocorticoids and retinoic acid on HIMeg cell proliferation were evaluated.It was found that the inhibitory effects of combinations of glucocorticoids and retinoic acid on HIMeg cell proliferation showed an additive property,suggesting that the regulation of GR expression by retinoic acid was of biological significance.
出处
《第二军医大学学报》
CAS
CSCD
北大核心
1994年第6期507-510,共4页
Academic Journal of Second Military Medical University
基金
国家自然科学基金
关键词
糖皮质激素
视黄酸
受体
白血病
巨核细胞系
glucocorticoid
retinoic acid
glucocorticoid receptor
mRNA
leukemia,megakaryoblastic lineage
