Ultrastructural transformation of gastric parietal cells reverting from the active to the resting state of acid secretion revealed in isolated rat gastric mucosa model processed by high-pressure freezing
Ultrastructural transformation of gastric parietal cells reverting from the active to the resting state of acid secretion revealed in isolated rat gastric mucosa model processed by high-pressure freezing
复制标题
DOI：
10.1093/jmicro/dfl004
复制
发表时间：
2006-04-01
期刊：
影响因子：
--
通讯作者：
Suganuma, Tatsuo
中科院分区：
文献类型：
--
作者：
Sawaguchi, Akira;Aoyama, Furniyo;Suganuma, Tatsuo
为了阐明胃壁细胞的功能转化，我们新建立了离体大鼠胃粘膜模型，其胃壁细胞从分泌酸的活跃状态恢复到分泌酸的静止状态。简单地说，在模型中预先刺激酸分泌后，用西咪替丁处理顶壁细胞，并通过光学显微镜下的低温冷冻或电子显微镜下的高压冷冻进行冷冻。结果，H+/K+- atp酶的免疫组织化学显示H'/K+- atp酶从根尖向细胞质区进行性易位。恢复期5min时的壁细胞超微结构与最大刺激时非常相似。然而，细胞内小管（IC）的顶端微绒毛不同程度地变成球根状，导致IC在恢复期60分钟完全闭塞。顶膜随后内化到细胞质中，形成独特的五层膜。有趣的是，在恢复期90分钟时，五层膜形成了许多多层自噬体，这些自噬体被强烈标记为H+/K+- atp酶。然后，顶壁细胞在105 min时显示出发育良好的高尔基体和溶酶体室室，并在120 min时恢复到它们的静止构象。与微绒毛超微结构变化相对应，ezrin免疫组化结果显示，在恢复期30min， ezrin与根尖区分离。本研究结果为胃壁细胞恢复到其静息构象的功能转化提供了新的见解。
To elucidate a functional transformation of gastric parietal cells, we have newly developed an isolated rat gastric mucosa model whose parietal cells exhibited a reverting process from the active to the resting state of acid secretion. Briefly, the parietal cells were treated with cimetidine following prior stimulation of acid secretion in the model, and cryofixed by plunge freezing for light microscopy or high-pressure freezing for electron microscopy. As a result, immunohistochemistry of H+/K+-ATPase demonstrated a progressive translocation of H'/K+-ATPase from the apical to the cytoplasmic region. The ultrastructure of parietal cells at 5 min in the reverting phase was quite similar to that of maximally stimulated one. However, the apical microvilli of intracellular canaliculi (IC) changed bulbous by degrees, resulted in complete occlusion of IC at 60 min in the reverting phase. The apical membranes were subsequently internalized into the cytoplasm forming unique penta-laminar membranes. Interestingly, at 90 min in the reverting phase, the penta-laminar membranes formed a number of multilamellar autophagosomes that were intensely labeled for H+/K+-ATPase. Then, the parietal cells exhibited well-developed Golgi apparatus and lysosomal compartments involving the multilamellar membranes at 105 min, and mostly reverted to their resting conformation at 120 min in the reverting phase. Corresponding to the ultrastructural changes of microvilli, the immunohistochemistry of ezrin showed a dissociation of ezrin from the apical region at 30 min in the reverting phase. The present findings provide new insights into the functional transformation in gastric parietal cells reverting to their resting conformation.