| Objective:By observing the capsaicin (capsaicin, CAP) on ethanol induced gastric mucosal injury in gastric acid secretion, antral area organizations capsaicin receptor (vanilloid receptor subtype 1, VR1) and calcitonin gene-related peptide (calcitonin gene-related peptide, CGRP) and substance P (substance P, SP) and the gastric mucosal barrier effect of CAP on ethanol induced gastric mucosal injury in rats and its mechanism. Methods:(1) Experimental animals grouping:Take 48 SD male rats weighing between 180g～240g, the rats are grouped into group A (control group), group B (ethanol model group), group C (CAP group), group D (Ethanol + CAP group), randomly with 12 rats in each group. (2) Animal treatment:The rats adapt to diet about 2 weeks before the initiation of experimentation. Then test in the following methods: setting up the experiment by intragastric administration.In group A:normal saline were divided into 2 times to use for 10mL/kg/d in the successive 2 weeks under ungiven free access to food and water.In group B:50% ethanol were divided into 2 times to use for 10mL/kg/d in the successive 2 weeks under ungiven free access to food and water.In group C:CAP were divided into 2 times to use for 5mg/kg/d in the successive 2 weeks under ungiven free access to food and water.In group D:CAP and ethanol were divided into 2 times to use for 5mg/kg /d and 10mL/kg/d in the successive 2 weeks under ungiven free access to food and water. All rats in the experiment are deprived of food but not prohibited from water for 24h before the end, and then proceed to specimen collection. (3) detection of indicators and methods:①Observe the rats's common states in the course of model and intragastric administration.②Gastric acid secration:All rats were anesthetized and opened the abdominal cavity, their stomachs were quickly ligated at the esophagus-gastric junction and antral and then removed,then washing with normal saline to collect cleaning fluid, the washed liquid was collected for detecting gastric acid output.③The expressions of VR1 and CGRP,sp in each rat's gastric antrum organization:Took a full-thickness organization of each rat's gastric antrum organization (about 0.5cm X 0.5cm) and dipped into 4% poly formaldehyde and fixed fully,then Paraffin-embedded, did a pathological section with the thickness of 0.5μm.The expression of VR1, CGRP and SP were detected with immunohistoche- mical method. Finally, Observed under the microscope and photoed.④Determination of gastric wall thickness of the gel layer: vertical cutting 1.6mm's thick sheet of gastric antrum wall thickness, these will be determination of the gel's layer thickness in dark field with an eyepiece micrometer under the inverted microscope.⑤The change of gastric mucosal barrier: The stomachs which were washed were dipped into 4% poly formaldehyde and fixed fully, gastric mucosa was observed through naked eyes and its injury was evaluated by Guth standard-modulated scores.Take out some gastric mucosa to do the histopathologic examination. Use the light microscope to observe gastric mucous membrane's injuring degree after the HE dyeing. The related data was checked with statistic method. Results:(1) General states:During the experiment, The rats in group A and C and D were in good state, acted smartly and their stools were basically normal. The rats in group B had emergence of aggressive, mutual bite sometime, but all the rats were no died. There are 4 rats in group B and 1 rats in group C and 2 rats in group D have been choking, but no suffocation and death. (2) The change of gastric acid secration: The levels of gastric acid secration in Group A,B,C,D were 48.27±2.14mmol/ L,49.23±3.14 mmol/L,34.12±2.09 mmol/L,35.19±3.08 mmol/L respectively. The gastric acid secration of group A and group B was significantly higher than group C and group D (P<0.05), there was not difference statistically significant between group C and group D (P> 0.05). (3) The expression of VR1 in gastric tissue:The expression leve of VR1 in rat's antral zone in group A,B,C,D were:0.62±0.49 scores,0.59±0.48 scores,2.61±0.34 scores,2.56±0.48 scores. The expression leve of VR1 in rat's antral zone in group C and group D were statistically significantly higher than group A and group B (p<0.05). There was not difference statistically significant between group A and group B (P> 0.05),it is the same between group C and group D (P> 0.05). (4) The expression of CGRP in gastric tissue: The expression leve of CGRP in rat's antral zone in group A,B,C,D were:1.06±0.43 scores,0.72±0.32 scores,2.19±0.57 scores,1.87±0.48 scores. The expression leve of CGRP in rat's antral zone in group B were statistically significantly lower than group A and group C and group D (p<0.05). The expression leve of CGRP in rat's antral zone in group A were statistically significantly lower than group C and group D (p<0.05),The expression leve of CGRP in rat's antral zone in group D were statistically significantly lower than group C (p<0.05). (5) The expression of SP in gastric tissue:The expression leve of SP in rat's antral zone in group A,B,C,D were: 0.51±0.49 scores,0.49±0.53 scores,0.76±0.48 scores,0.75±0.25 scores.The expression of SP in group C were slightly higher but not statistically significant than the group A (P> 0.05);the expression of SP in the rest of the group were not statistically significant. (6)gastric gel layer thickness:the thickness of rat gastric gel layer in group A,B,C,D were 72.22±6.21μm,41.76±5.28μm,71.34±4.87μm,60.28±5.27μm.. The thickness of rat gastric gel layer in group B were statistically significantly lower than group A and group C and group D (p<0.05), the thickness of rat gastric gel layer in group D were statistically significantly lower than group A and group C (p<0.05),the thickness of rat gastric gel layer in group A were statistically significantly lower than group A and group C (p<0.05),the thickness of rat gastric gel layer in group A were not statistically significant than group C(P>0.05). (7)gastric mucosal's barrier:①the damage of gastric mucosal by macroscopic:The gastric of group A and group C were smooth, group B's gastric show hyperemia, punctate erosion. Group D' gastric mucosa shows congestion, no erosion.The score of gastric mucosal injury (Guth standard modified score) in group A,B,C,D were:0,27.42±3.61 score, 0,9.21±2.32 score. Mucosal injury's score in group B was significantly greater than A,C, D(p<0.05).Mucosal injury's score in group D was significantly greater than A,C (p<0.05).②The change of rat gastric mucosa pathological: group A and group C' gastric mucosa were normal epithelial cells, arranged in neat rows, and no mucosal loss, congestion, edema, inflammatory cell infiltration and glandular disorganization and necrosis. The gastric mucosal of group B surface microscopy, epithelial damage, shedding, mucosal edema, neutrophil infiltration, even visible ulcer lesions. The gastric mucosal of group D epithelial cells with mild loss, congestion, edema, and no disturbance of glandular structure and epithelial cell necrosis, inflammatory cell infiltration. Injury of rat gastric mucosa pathology points (Masuda standard method) in group A,B,C,D were: 0.12±0.38 score,3.91±1.10 score,0.11±0.25 score,1.21±0.28 score. The group B's pathological tissue damage was significantly greater than the group A, C, D (p<0.05), the damage of pathological tissue in group D was significantly greater than A, C (p<0.05), the damage of pathological tissue between group A and group C was not statistically significant (P> 0.05).Conclusion:1.Intragastric administration of ethanol can be successfully established the model of gastric mucosal injury in rats; 2. Intragastric administration of CAP with 5mg/kg/d can reduced the acid secretion in gastric in rats which injurying by ethanol; 3. Intragastric administration of CAP with 5mg/kg/d can improve gastric mucosal's thickness of gel layer in rats which injurying by ethanol; 4. CAP 5mg/kg/d intragastric administration can improve gastric mucosal injury in rats which injurying by ethanol; 5. CAP reduce gastric acid secretion and protect gastric mucosal's gel layer may be related with CGRP, no significant correlation with the SP.
|
PDF Full Text Request