Effects of aspirin on tight junction structure of the canine gastric mucosa

The effect of aspirin and smoking on urinary excretion profiles of lactulose and mannitol in young women: toward a dynamic, aspirin augmented, test of gut mucosal permeability

“…The prompt and sustained elevation of lactulose after various doses (100–325 and 1300 mg) of aspirin has been described in previous studies 19–22 and fits in with reports of the effects of aspirin on the cellular actin cytoskeleton 51 and tight junction integrity 52 . The relative invariance of this response over the 6‐h experimental period suggests that it is less likely to be affected by minor variations in sampling period, although the general increase in excretion rate with increase in sampling time indicates a similar ongoing change to that reported by Rao et al.…”

Enantiomers of flurbiprofen can distinguish key pathophysiological steps of NSAID enteropathy in the rat

“…The drugs were given in different quantities (0.5 ml of 3 mM DNP and 1 ml of 12 mM flurbiprofen) and there may be differences in pharmacokinetic factors (rate and site of absorption) between DNP and flurbiprofen due to their different physicochemical properties. The in vivo electron microscopy changes of mitochondria following DNP and flurbiprofen were nevertheless almost identical to those reported to be caused by aspirin in mouse and canine stomach,52 53 and alcohol and bile acids, both of which are potent uncouplers of oxidative phosphorylation, in mouse stomach 5455 Whether the concentrations required for uncoupling to occur in vitro (0.03–1.0 mmol)29 30 50 51 are achieved in vivo within the intestinal mucosa following therapeutic oral administration of NSAIDs has not been determined directly, but a mechanism for NSAID accumulation within epithelial cells during absorption has been proposed previously by the “ion trapping” hypothesis 24…”

Prophylactic Effect of Rebamipide on Aspirin-Induced Gastric Lesions and Disruption of Tight Junctional Protein Zonula Occludens-1 Distribution

“…In 1986, Meyer et al reported the morphological change of tight junctions in the canine gastric epithelial cells after aspirin treatment by using light microscopy, freeze-fracture electron microscopy, and extracellular tracer transmission electron microscopy techniques. Interestingly, its tight junctional changes are induced within few minutes with no relation to dosage and exposure time to aspirin (62). So they concluded that the impairment of tight junction complexes between viable gastric mucosal epithelial cells may be a major contributing factor in the etiology of aspirin-induced gastric lesions.…”