| [ Summary ] |
Proton pump inhibitors block H+, K+-ATPase activity by binding to the enzyme after being converted into sulfenamide derivatives in parietal cells. Vacuolation of parietal cells may emerge with long term use of PPI. Swelling of intracellular canaliculi and lysozyme activity may also be involved. Hypergastrinemia is involved in the development of gastric ECL carcinoid tumors in rats, but no such tumors are found in humans after long term PPI usage, because of the low number of ECL cells in the human stomach. Moreover, hypergastrinemia, caused by long term administration of PPI may be involved in proliferation in the gastric mucosa. Long term PPI administration, however, could produce atrophy of the gastric mucosa in H. pylori-induced chronic gastritis. Though PPI may decrease gastric mucous, no serious adverse effects are noted after long term PPI administration. |