Seybold J, Bieger W, Kern H F
Virchows Arch A Pathol Anat Histol. 1975 Nov 28;368(4):309-27. doi: 10.1007/BF00432309.
The possible role of microtubules and microfilaments in the secretory process of the rat exocrine pancreas was analysed in vitro using isolated pancreatic lobules. Colchicine and vinblastine as microtubule inhibitors, hexylene glycol as a microtubule stabilizer, and cytochalasin B as a disruptive agent for microfilaments were used in increasing concentrations to test their effects on protein synthesis, intracellular transport, zymogen discharge, and cellular respiration. Colchicine only at 10(-2) M concentrations inhibits protein synthesis, while vinblastine inhibits at 10(-6) and 10(-5) M by 20% and at 10(-4) M by 55%. A similar inhibition is observed with 1.5% concentrations of hexylene glycol while cytochalasine B at 1,5 and 10 mug/ml is without effect on protein synthesis. Colchicine and vinblastine have their major effects on intracellular transport both in secretion studies and cell fractionation experiments. Colchicine in concentrations between 10(-3) to 10(-5) M inhibits discharge of newly synthesized proteins by 50%, while vinblastine shows a dose-response relationship of 40% inhibition of 10(-6) M to 90% at 10(-4) M. Discharge of amylase is uniformly reduced by 30% by both colchicine and vinblastine in the whole dose range. The pronounced effect of colchicine and vinblastine is evident in cell fractionation studies: both drugs inhibit the disappearance of protein radioactivity from microsomes and its appearance in zymogen granules; similarly the peak radioactivity in smooth microsomes (Golgi) appears delayed. No differential effect on the secretory process was observed with 1.5% concentrations of hexylene glycol or cytochalasin B at 1.5 and 10 mug/ml concentrations. A fines tructural analysis of microtubules and microfilaments in the exocrine pancreatic cell reveals their distribution in all parts of the cytoplasm and in relation to all cell organelles. Both systems (microtubules, microfilaments) seem to be connected, at least in certain areas of the cytoplasm and at the plasma membrane. The reduction of transport efficiency by microtubule inhibitors results in a deposition of secretory material in the cristernal space of the rough endoplasmatic reticulum, which leads to the formation of paracrystals. Colchicine at 10(-3) M concentrations leads to an enlargement of condensing vacuoles in the Golgi complex.
利用离体胰腺小叶在体外分析了微管和微丝在大鼠外分泌胰腺分泌过程中的可能作用。使用秋水仙碱和长春花碱作为微管抑制剂，己二醇作为微管稳定剂，细胞松弛素B作为微丝破坏剂，以递增浓度来测试它们对蛋白质合成、细胞内运输、酶原分泌和细胞呼吸的影响。仅10⁻²M浓度的秋水仙碱抑制蛋白质合成，而长春花碱在10⁻⁶M和10⁻⁵M时抑制20%，在10⁻⁴M时抑制55%。1.5%浓度的己二醇也观察到类似的抑制作用，而1、5和10μg/ml浓度的细胞松弛素B对蛋白质合成无影响。秋水仙碱和长春花碱在分泌研究和细胞分级分离实验中对细胞内运输均有主要影响。10⁻³至10⁻⁵M浓度的秋水仙碱抑制新合成蛋白质的分泌达50%，而长春花碱呈现剂量反应关系，10⁻⁶M时抑制40%，10⁻⁴M时抑制90%。在整个剂量范围内，秋水仙碱和长春花碱均使淀粉酶分泌均匀减少30%。秋水仙碱和长春花碱在细胞分级分离研究中的显著作用很明显：两种药物均抑制蛋白质放射性从微粒体消失及其在酶原颗粒中出现；同样，平滑微粒体（高尔基体）中的放射性峰值出现延迟。1.5%浓度的己二醇或1.5和10μg/ml浓度的细胞松弛素B对分泌过程未观察到差异作用。对外分泌胰腺细胞中的微管和微丝进行的精细结构分析揭示了它们在细胞质所有部分以及与所有细胞器相关的分布情况。两个系统（微管、微丝）似乎至少在细胞质的某些区域以及质膜处相互连接。微管抑制剂导致运输效率降低，致使分泌物质沉积在内质网的嵴间隙中，进而形成副晶体。10⁻³M浓度的秋水仙碱导致高尔基体复合体中浓缩泡增大。
