Kobayashi A, Araki K, Ando T, Ogata T
Department of Surgery, Kochi Medical School, Japan.
Arch Histol Cytol. 1997 Jun;60(2):205-14. doi: 10.1679/aohc.60.205.
The presence of subunit proteins, 1H9 for the alpha-subunit and 2B6 for the beta-subunit, of H(+)-K+ ATPase and its activity in tubulovesicles and intracellular canaliculi of gastric parietal cells were immunocytochemically and enzyme cytochemically examined. Specimens were taken from healthy human volunteers by endoscopic biopsy in resting, tetragastrin-stimulated and omeprazole-inhibited conditions. H(+)-K+ ATPase was present in both intracellular canaliculi and tubulovesicles in these three conditions. Gold particles of the alpha-subunit decreased in number, and those showing the beta-subunit increased under both gastrin-stimulating and omeprazole-inhibiting conditions compared with parietal cells in the resting state. We suggest that the administration of tetragastrin and omeprazole alter the turnover rate of each subunit of H(+)-K+ ATPase, resulting in the difference of the proportions of alpha- and beta-subunits. Moreover, the activity of H(+)-K+ ATPase was detected strongly beneath the membrane of microvilli and weakly in that of tubulovesicles under these three conditions. After 7 days of daily oral omeprazole intake, H(+)-K+ ATPase in parietal cells were detected in intracellular canaliculi and tubulovesicles. However, the H(+)-K+ ATPase activity in tubulovesicles was diminished 1 h after omeprazole intake, and the activity in intracellular canaliculi was completely inhibited even 3 h after omeprazole administration. These results show that omeprazole inhibited the H(+)-K+ ATPase activity in both intracellular canaliculi and tubulovesicles.
采用免疫细胞化学和酶细胞化学方法，检测胃壁细胞H(+)-K+ATP酶α亚基的1H9和β亚基的2B6亚单位蛋白的存在及其在微管泡和细胞内小管中的活性。在静息、四肽胃泌素刺激和奥美拉唑抑制状态下，通过内镜活检从健康人类志愿者获取标本。在这三种状态下，细胞内小管和微管泡中均存在H(+)-K+ATP酶。与静息状态下的壁细胞相比，在胃泌素刺激和奥美拉唑抑制状态下，α亚基的金颗粒数量减少，而显示β亚基的金颗粒数量增加。我们认为，四肽胃泌素和奥美拉唑的给药改变了H(+)-K+ATP酶各亚基的周转率，导致α和β亚基比例的差异。此外，在这三种状态下，微绒毛膜下检测到较强的H(+)-K+ATP酶活性，而微管泡膜中的活性较弱。每日口服奥美拉唑7天后，在细胞内小管和微管泡中检测到壁细胞中的H(+)-K+ATP酶。然而，奥美拉唑摄入后1小时，微管泡中的H(+)-K+ATP酶活性降低，甚至在奥美拉唑给药3小时后，细胞内小管中的活性也被完全抑制。这些结果表明，奥美拉唑抑制了细胞内小管和微管泡中的H(+)-K+ATP酶活性。
