erties of EOHM Effect of EOHM on acetic acid-induced gastric ulcer. Oral administration of EOHM for 14 Histological analysis The HE MEK 162 staining revealed the presence of an ulcer penetrating the wall caused by gastric mucosa damage induced by 30% acetic acid and confirmed the gastroprotective action of EOHM or pantoprazole after 14 days of treatment, with significant regeneration of the gastric mucosa. consecutive days of treatment, significantly decreased the area of chronic ulcer to 9.962.2 mm2 compared to the control group treated with 1% Tween-80 aqueous solution, in 6 
Gastroprotective Effects of Hyptis martiusii PAS staining also revealed the presence of gastric mucus and the arrangement of intact glands in the groups treated with pantoprazole or EOHM. Discussion In this study we investigated the cytoprotective mechanisms that may be involved in the gastroprotective effect of the essential oil of Hyptis martiusii, such as its effect on mucus production, the role of nitric oxide and sulfhydryl groups, the possible antioxidant activity and its healing action regarding acetic acid-induced chronic ulcer. We also tried to clarify the possible mechanism of action responsible for the inhibition of gastric acid effect of EOHM. Data from the literature have demonstrated experimentally that a large number of essential oils of aromatic and medicinal plants possess gastroprotective 26148857 and ulcer healing properties. In essential 6882442 oils in general, the major constituents are monoterpenes and sesquiterpenes, and this applies to species of the genus Hyptis where these constituents are identified as the main components. Confirming these data, the chemical characterization of the essential oil of Hyptis martiusii identified 26 components and between monoterpenes and sesquiterpenes the main constituents were 1,8-cineole, d-3-carene, camphor, a-pinene and caryophyllene oxide. In a study previously reported by us, the phytochemical characterization of the essential oil identified 24 components, presenting as major components bicyclogermacrene, trans-caryophyllene, caryophyllene oxide, 1,8-cineole, d-3-carene and ledene. Immunohistochemical analysis The gastric tissues obtained in the acetic acid-induced gastric ulcer model were used for immunohistochemical localization of PCNA antibody. In 7 Gastroprotective Effects of Hyptis martiusii In the current analysis, we have observed differences in the quantity, chemical composition and yield of these same constituents. For example, there was no bicyclogermacrene and the percentage of various constituents. Such variations may be due to environmental factors, such as temperature, humidity, exposure to sun, wind regimes, and others factors that may affect chemical composition of the essential oils. Despite the differences between the chemical composition, the essential oil of Hyptis martiusii continued exerting its gastroprotective effect. Moreover, since the essential oil is a complex mixture of chemical compounds, we cannot ensure that the gastroprotective activity is associated with a specific chemical compound, but it is possibly a synergic effect of the various components. Recently, data from our laboratory showed that the essential oil of Hyptis martiusii leaves displayed a significant gastroprotective effect on different models of gastric lesions in Wistar rats. In this same study, the intraduodenal administration of the essential oil was able to decrease basal acid secretion in the gastric mucosa in rats with the