The pathophysiology of acute gastric ulcer development in normotensive and hypertensive rats: A comparative study

Although gastric ulcers and hypertension are diseases that affect a large part of the population, the association of these comorbidities is still poorly studied. Therefore, the present study investigated the response of normotensive (NTR) and spontaneously hypertensive (SHR) rats to gastric ulcers induced by indomethacin or ethanol. For that, adult male and female NTR and SHR received indomethacin (100 mg/kg, p.o) or ethanol P.A (5 ml/kg, p.o) to induce gastric ulcer, after the pre-treatment with prostaglandin E₂ (PGE₂) and carbenoxolone (CBX), respectively. The results revealed that, when compared to NTR, the SHR, both male and female, showed lower lesion area indexes when exposed to indomethacin. On the other hand, ethanol caused an area of lesion approximately 60% larger in the male and female SHR in comparison with the NTR. Significantly, the pre-treatment with PGE₂ or CBX prevented the gastric ulcer damage promoted by indomethacin or ethanol, respectively. The histological analyses of the gastric mucosa from ethanol-induced ulcer revealed severe disruption of gastric architecture and bleeding points, that have been exacerbated in the SHR group. The gastric tissue from the SHR group also showed high levels of nitrite, a marker of nitric oxide production, which was accompanied by an increase in lipid hydroperoxide levels, an important biomarker of oxidative damage, in comparison with NTR. Taking together, the results of the present study showed important differences in the development of gastric ulcer between NTR and SHR. Further studies are needed for an in-depth analysis of the pathophysiological mechanisms involved in these responses.