Spindler-Barth M, Spindler K D
Lehrstuhl für Hormon- und Entwicklungsphysiologie, Heinrich-Heine-Universität Düsseldorf, Germany.
In Vitro Cell Dev Biol Anim. 1998 Feb;34(2):116-22. doi: 10.1007/s11626-998-0093-y.
Chironomus tentans cells were cultured in the presence of gradually increasing concentrations of 20-OH-ecdysone or a nonsteroidal molting hormone agonist, the benzoylhydrazine RH 5992, for a period of about 2 yr. From these cultures, subclones were selected, which are resistant to up to 25 microM 20-OH-ecdysone according to morphological (changes in cell shape and cell arrangement) and physiological criteria (acetylcholinesterase induction, secretion of chitinolytic enzymes, thymidine incorporation). Some subclones, selected in the presence of 20-OH-ecdysone, are resistant only to molting hormone, but still respond to RH 5992 morphologically and biochemically, whereas subclones selected in the presence of the benzoylhydrazine showed no reaction neither to 20-OH-ecdysone nor to the hormone agonist. Hormone resistance is stable; 3 mo. after hormone withdrawal, resistant clones still do not respond to renewed exposure to 20-OH-ecdysone or RH 5992, respectively. Because in all resistant subclones tested so far all hormonally regulated responses known from sensitive cells were no longer detectable, it is assumed that the hormone signaling pathway itself is interrupted. Possible mechanisms of hormone resistance were discussed.
将摇蚊细胞在20-羟基蜕皮激素或非甾体蜕皮激素激动剂苯甲酰肼RH 5992浓度逐渐增加的条件下培养约2年。从这些培养物中挑选出亚克隆，根据形态学标准（细胞形状和细胞排列的变化）和生理学标准（乙酰胆碱酯酶诱导、几丁质分解酶分泌、胸腺嘧啶核苷掺入），这些亚克隆对高达25μM的20-羟基蜕皮激素具有抗性。一些在20-羟基蜕皮激素存在下挑选出的亚克隆仅对蜕皮激素有抗性，但在形态学和生化方面仍对RH 5992有反应，而在苯甲酰肼存在下挑选出的亚克隆对20-羟基蜕皮激素和激素激动剂均无反应。激素抗性是稳定的；在撤除激素3个月后，抗性克隆分别对再次暴露于20-羟基蜕皮激素或RH 5992仍无反应。由于在迄今为止测试的所有抗性亚克隆中，敏感细胞中已知的所有激素调节反应均不再能检测到，因此推测激素信号通路本身被中断。文中讨论了激素抗性的可能机制。
