Abstract:
1. Myo-inositol (MI) is an essential metabolite for cell function in animals and humans. The aim of this study was to characterise the transport mechanism of MI in the small intestine of laying hens as there is a lack of knowledge about the MI uptake mechanisms. The hypothesised secondary active, cation coupled transport of MI was assessed by electrophysiological measurements with Ussing chambers, and was compared to the electrophysiology of glucose transport.2. Twenty-six laying hens were used. The potential ion-dependent transport was tested in tissue of the small intestine. Barrier function of the tissue was shown by determining the transepithelial resistance. During the experiments, mucosal and serosal buffers were sampled to measure time-dependent changes in MI concentrations. Samples from eight hens were further used for Western blot analyses of the jejunal apical membranes.3. Active MI transport, indicated by changes in the short circuit current after MI addition, could not be demonstrated in the Ussing chambers experiments. MI was further not detectable in the serosal buffer, nor in the lysates of mucosal tissue cytoplasm nor lipids. Thus, there was no evidence for a MI transport or absorption. However, Western blot analyses of the jejunal apical membrane revealed signals indicated the expression of the MI transport proteins SMIT-1 and SMIT-2.4. In conclusion, the MI transport process in the chicken intestine is more complex than it was presumed and is probably influenced by still unknown regulations or metabolic processes.
摘要:
1.肌醇(MI)是动物和人类细胞功能的必需代谢产物。这项研究的目的是表征MI在蛋鸡小肠中的运输机制,因为缺乏有关MI摄取机制的知识。假设的次要活动,MI的阳离子耦合转运通过用Ussing室进行电生理测量来评估,并与葡萄糖运输的电生理学进行了比较。2。使用了26只蛋鸡。在小肠组织中测试了潜在的离子依赖性转运。通过确定跨上皮阻力显示了组织的屏障功能。在实验过程中,对粘膜和浆膜缓冲液进行取样,以测量MI浓度的时间依赖性变化.来自八只母鸡的样品进一步用于空肠顶端膜的Western印迹分析。活动MI传输,由MI添加后短路电流的变化指示,在Ussing室实验中无法证明。在浆膜缓冲液中进一步检测不到MI,在粘膜组织细胞浆或脂质的裂解物中也没有。因此,没有MI转运或吸收的证据.然而,空肠顶膜的Western印迹分析显示信号表明MI转运蛋白SMIT-1和SMIT-2.4的表达。总之,鸡肠中的MI转运过程比推测的要复杂得多,可能受到未知的调控或代谢过程的影响.