Mucin exocytosis.
Mucin exocytosis.
复制标题
粘蛋白胞吐作用。
DOI：
10.1164/ajrccm/144.3_pt_2.s33
复制
发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Verdugo,P
中科院分区：
文献类型：
--
作者：
Verdugo,P
由呼吸道粘膜杯状细胞产生的粘蛋白在储存于分泌颗粒中时被浓缩。粘蛋白的凝聚及其在eX 0 CYt 0 sis时的去凝聚可以用聚合物凝胶相变理论来解释。在分泌孔打开后，颗粒内的Ca 2+被交换为细胞外的Na+。Na/Ca交换引发聚合物凝胶相变，由此粘蛋白聚合物基质经历大量溶胀，从而从凝聚相变为水合相。颗粒内容物的溶胀由唐南势驱动，并导致分泌产物的释放和小粘蛋白凝胶的形成，其随后彼此退火以形成呼吸道粘液。由于粘蛋白网络的缠结而不是交联的拓扑结构，呼吸道粘液的流变特性主要取决于水合作用。由于粘蛋白是多离子的，粘液的水合作用由唐南平衡控制。因此，粘液水合作用和流变性由两个因素决定：分泌的粘蛋白的量、链长和电荷密度，以及穿过呼吸道粘膜运输的水的量和离子和多离子组成。AM修订版DIS 1991; 144：S33-S37
Mucins produced by goblet cells of the respiratory mucosa are condensed while stored in secretory granules. Mucin condensation and its decondensation upon eX0CYt0sis can be explained by the theory of polymer gel phase transition. After the opening of a secretory pore, Ca2+ inside the granule is exchanged for extracellular Na+. Na/Caexchange triggers a polymer gel phase transition whereby the mucin polymer matrix undergoes massive swelling and thereby changes from a condensed to a hydrated phase. Swelling of the granular content is driven by a Donnan potential and results in the release of secretory product and the formation of small mucin gels, which later anneal to each other to form the respiratory mucus. Because of the tangled rather than cross-linked topology of the mucin network, the rheologic properties of the respiratory mucus depend primarily on hydration. As mucins are polyionic, the hydration of mucus is controlled by a Donnan equilibrium. Hence, mucus hydration and rheology are determined by two factors: the quantity, chain length, and charge density of the secreted mucins, and the amount and the ionic and polyionic composition of the water transported across the respiratory mucosa. AM REV RESPIR DIS 1991; 144: S33-S37