BACKGROUND:Bile, which is secreted by the liver, is essential for digesting fat and maintaining homeostasis. Although the rheology of bile is very important to its flow, its extensional viscosity has not been studied. OBJECTIVE:We investigated the stretching of bile and evaluated its extensional viscosity using a filament-breakup device. METHODS:A liquid bridge formed between the endplates of the filament-breakup device. The midpoint diameter of the bridge was recorded by a laser micrometer. The filament self-thinning was captured by a high-resolution, high-speed camera. We used the liquid bridge diameter to evaluate the extensional viscosity of bile. RESULTS:All samples show shear-thinning and viscoelasticity. Bile sediment has much greater viscosity and stretches more than bile solution. Filament thinning takes a long time for bile sediment and a short time for solution. The global function for the mid-filament diameter can be used to predict the evolution of the filament diameter of the liquid bridge and the trend of the extensional viscosity of bile. CONCLUSIONS:The extensional viscosity of bile is much greater than its shear viscosity. Because mucus concentration makes bile sediment more viscous than the solution, bile viscosity can increase sharply, thereby increasing risks of such diseases as gallstones and sludge buildup in the biliary system.

中文翻译：

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胆汁的拉伸行为和拉伸粘度。

背景：由肝脏分泌的胆汁对于消化脂肪和维持体内平衡至关重要。尽管胆汁的流变性对其流动非常重要，但尚未研究其拉伸粘度。目的：我们研究了胆汁的拉伸，并使用细丝分解装置评估了其拉伸粘度。方法：在细丝分解装置的端板之间形成一个液桥。用激光测微计记录桥的中点直径。细丝的自稀化是通过高分辨率，高速相机捕获的。我们使用液桥直径评估胆汁的拉伸粘度。结果：所有样品均显示出剪切稀化和粘弹性。胆汁沉积物比胆汁溶液具有更大的粘度和更大的伸展性。细丝沉积对于胆汁沉积物来说花费很长时间，而对于溶解则花费时间很短。中丝直径的全局函数可用于预测液桥丝直径的演变和胆汁延伸粘度的趋势。结论：胆汁的拉伸粘度远大于其剪切粘度。由于粘液浓度使胆汁沉积物比溶液更粘稠，因此胆汁粘度会急剧增加，从而增加胆石系统中胆结石和污泥堆积等疾病的风险。胆汁的拉伸粘度远大于其剪切粘度。由于粘液浓度使胆汁沉积物比溶液更粘稠，因此胆汁粘度会急剧增加，从而增加胆石系统中胆结石和污泥堆积等疾病的风险。胆汁的拉伸粘度远大于其剪切粘度。由于粘液浓度使胆汁沉积物比溶液更粘稠，因此胆汁粘度会急剧增加，从而增加胆石系统中胆结石和污泥堆积等疾病的风险。