Calicum channel blockers and prostaglandin generation by gastric surface epithelial cells

Mechanisms of cytoprotective effect of amino acids on local toxicity caused by sodium laurate, a drug absorption enhancer, in intestinal epithelium

“…Rather than the influx across the plasma membrane, the release from the intracellular store was suggested as a mechanism in the case of C10 33. However, this explanation is still controversial because it has also been reported that neither ethanol treatment40,41 nor heat shock42 cause an increase in [Ca 2+ ] i (and even cytotoxicity) in the Ca 2+ ‐free medium, whereas they do cause such an increase in the presence of Ca 2+ . Our future studies will focus on the investigation of the mechanisms by which C12 increases and amino acids decrease [Ca 2+ ] i .…”

Amino Acids Protect Epithelial Cells From Local Toxicity by Absorption Enhancer, Sodium Laurate

“…As a possible mechanism, the perturbation of intracellular Ca 2+ homeostasis may be involved. An injury caused by oxidative stress was reported to relate to the high level of Ca 2+ in the cytosol in 1980s40–42 and recently it has been reported that the cytoprotection and/or the healing of the gastric mucosa, in which prostaglandins are involved, is ascribed to the action of prostaglandins, not to the increase in the level of Ca 2+ in the cytosol 43–45. Our further studies for clarification of the mechanisms behind the cytoprotective action by amino acids will be focused on its relationship with HSPs and Ca 2+ level in the cytosolic compartment of the colon.…”

Prostaglandin-lnduced Protection of Cultured Rat Gastric Cells against Ethanol Is Inhibited by a Microtubule Inhibitor

“…The protective effect of dmPGE2 on gastric mucosal cells from damage caused by various noxious agents such as aspirin, taurocholate, and ethanol has been found in in vitro studies [1-4, 8,9], Fukuda et al [5] have shown that extracellular calcium potentiates damage caused by etha nol to dispersed surface epithelial cells isolated from rat gastric mucosa, and that verapamil, a phenylalkylaminesensitive calcium channel blocker, inhibits ethanol-in duced cell damage. Konda et al [6] have demonstrated that ethanol stimulates the influx of calcium into dis persed chief cells from guinea pig stomach by opening La-1+-sensitive calcium channels, thus damaging the cells.…”

“…Since several studies suggest the important role of calcium in cell injury [5,6], we performed experiments in the presence and absence of extracellular calcium.…”