# _Brassica oleraea_ Pevents HCl/Ethanol-Induced Gastric Damages in Mice
## 3 Results
### BOE Attenuates Mucus Loss Induced by H/E  
To explore the effect of BOE on integrity of the gastric mucus, we determined the mucus content via Alican blue binding assay. In parallel with results from histopathology, pre-administration of BOE significantly attenuated H/E-mediated loss of gastric mucus in a dosage-dependent manner (Figure 4a). RA also significantly prevented the mucus loss, and its effect did not differ from that seen in response to 50 mg/kg BOE. Next, we quantified the level of carbohydrates in the gastric mucus. Compared to the vehicle, H/E significantly decreased the levels of total hexose and sialic acid, suggesting that H/E damages glycoprotein in the gastric mucus. By contrast, 50-100 mg/kg BOE as well as RA significantly blocked the decreases in the level of total hexose and sialic acid. However, the carbohydrate levels by 25 mg/kg BOE did not differ from those by H/E (Figure 4b). Compared between H/E + BOE and H/E + RA group, the magnitude of the sialic acid's restoration by 100 mg/kg BOE was only greater than that by RA (\(p<0.01\)). In addition, 50-100 mg/kg BOE and RA significantly prevented the H/E-mediated decrease in collagen (Figure 4c), which is a representative structural protein found in the extracellular matrix [27]. There were no statistical differences in collagen content between the group treated with three different doses of BOE and RA.  
BOE Decreases Histamine in the Plasma and Reduces mRNAs Expression Associated with Secreting Gastric Acid  
Because it has been reported that ethanol decreases gastric pH in experimental animals [28], we further explored the effect of BOE on the major regulating factors for secreting gastric acid. Compared to vehicle, H/E significantly increased plasma level of histamine. Although pre-administration of RA did not attenuate H/E-mediated increase in plasma histamine, 50-100 mg/kg BOE significantly decreased plasma histamine level, relative to H/E group (Figure 5a), and the magnitude of the reduction in histamine level by 100 mg/kg BOE was greater than that by RA (\(p<0.05\)). Real-time PCR analysis was conducted to  
Figure 2: Macroscopic effect of BOE on H/E-mediated gastric damage. (**a**) Representative gross stomach images. Scale bars indicate 6.5 mm. (**b**) Macroscopically visible lesion on the gastric mucosa was quantified as a gross lesion area (mm\({}^{2}\)). Numerical results are presented as mean \(\pm\) SD of ten mice (**_p_ \(<0.01\) between the vehicle and H/E groups; **_p_ \(<0.01\) versus H/E-administered group). BOE, _B. olerca_ var. _capitata_ L. extract; Car., cardiac region of the stomach; Fun., fundus/corpus region of the stomach; H/E, HCl/ethanol; Pyl., pylorus region of the stomach; RA, ranitidine hydrochloride.  
assess the effects of BOE on major responsible genes for secreting gastric acid. In parallel with the result from plasma histamine, H/E significantly induced mRNA expression levels of H2R, CCK2R, and H\({}^{+}\)/K\({}^{+}\) ATPase. However, H/E-mediated increases in those mRNAs were significantly inhibited by the three different doses of BOE, except for H\({}^{+}\)/K\({}^{+}\) ATPase mRNA, which did not differ significantly between H/E and H/E + BOE (25 mg/kg) group. In addition, mRNA levels of H2R and CCK2R, but not H\({}^{+}\)/K\({}^{+}\) ATPase, were also reduced by pre-administration of RA, and decreases in H2R and CCK2R mRNAs by RA did not differ from those by 50-100 mg/kg BOE (Figure 5b).