摘要
目的 :研究生长抑素 (somatostatin,SS)对人结肠癌细胞株的生长调控及受体后的信息传导途径。方法 :以不同浓度的生长抑素处理人低分化结肠癌细胞株 Clone A细胞 ,观察细胞的生长情况 ;先分别提取细胞内三磷酸肌醇 (inositol1,4,5 - trisphosphate,IP3)及环磷酸腺苷 (cyclic adenosine m onophosphate,c AMP) ,分别应用液体闪烁测量法、γ-闪烁记数仪测定其含量 ;用 Fura- 2负载及荧光测定细胞内游离 Ca2 +浓度 ([Ca2 + ]i) ;分别提取细胞浆及细胞膜中的蛋白激酶 C(protein kinase C,PKC) ,参考 Takai法测定其活性。结果 :不同浓度的生长抑素 (10 - 1 0～ 10 - 5 m ol/ L )能明显抑制 Clone A细胞的生长 ,且呈剂量依赖关系 ;生长抑素能显著地抑制 Clone A细胞内 IP3、[Ca2 + ]i、c AMP的生成和 PKC活性。结论 :生长抑素抑制人低分化结肠癌细胞株 Clone A的生长 ,可能通过磷酸肌醇途径 ,使细胞内 IP3和 [Ca2 + ]i 减少或通过抑制 PKC活性而抑制细胞生长 ;另一方面可能通过腺苷环化酶途径 ,使细胞内 c AMP减少 ,抑制 c AMP依赖的蛋白激酶 。
Objective:Our purpose was to investigate the growth regulation and postreceptor signal transduction of somatostatin (SS) on human colon cancer cell line. Methods:Low differentiated clone A cells of human carcinoma were treated with different concentrations of SS and the growth status was observed. Intracellular 1,4,5 trisphosphate (IP 3) and cyclic adenosine monophosphate (cAMP) were extracted, then the concentrations of them were measured by liquid scintillation technique and gamma scintillation counter.Intracellular free calcium concentration was detected by loading Fura 2 and fluorescental technique. Protein kinase C (PKC) was extracted from cytosol and membrane, then the activity of both parts was determined with TaKai method. Results:The clone A cell growth was inhibited greatly by different concentrations of SS (10 -10 to 10 -5 mol/L) and it is related to the doses of SS.Somatortatin could largely inhibit the production of intracellular IP 3, [Ca 2+ ] i, and cAMP, and decrease the activity of PKC. Conclusion:The growth of Clone A cell can be inhibited by SS. The inhibition may be mediated by phosphate inositol pathway, so intracellular IP 3, [Ca 2+ ] i decreased, or inhibited the cell growth by inhibiting the activity of PKC.On the other hand, the cell proliferation may be inhibited by adenosine cyclase pathway, that is decreasing intracellular cAMP ,inhibiting cAMP depending protein kinase.
出处
《中国医科大学学报》
CAS
CSCD
北大核心
2001年第1期33-35,共3页
Journal of China Medical University
关键词
结肠癌
生长抑素
细胞株
调控
受体
信息传导
somatostatin
human
colon cancer cell line
inositol 1,4,5 trisphosphate
intracellular free calcium
cyclic adenosine monophosphate
protein kinase C
