Abstract
Objective To investigate the effects and mechanism of nobiletin(NOB)on slow transit constipation(STC)in rats through dopamine receptor D2(DRD2).Methods A total of 70 SD rats were randomly divided into blank group,model group,experimental-L,M,H group,AAV9-NC group and AAV9-DRD2 group,with 10 rats in each group.STC model was established with 15 mg·kg-1 compound diphenoxylate by intragastric administration except in blank group.In experimental-L,M,H group,0.1,0.2,0.4 g·kg-1 NOB was administered intragastricly.On the basis of experimental-M group,AAV9-NC group and AAV9-DRD2 group were given AAV9-NC and AAV9-DRD2100 μL,respectively.Weight and fecal indexes of rats were detected.The expression levels of DRD2 was detected by quantitative real time polymerase chain reaction.Vasoactive intestinal peptide(VIP)and nitric oxide(NO)levels were detected by enzyme-linked immunosorbent assay.Levels of AMP-activated protein kinase(AMPK)/endothelial nitric oxide synthase(eNOS)signaling pathway related proteins were detected by Western blot.Results The fecal water content in blank,model,and experimental-L,M,H groups were(35.24±5.25)％,(24.76±3.47)％,(28.38±2.77)％,(32.76±3.49)％and(33.32±4.34)％,respectively;the fecal quantity were(53.20±5.25),(42.40±4.55),(47.10±5.36),(49.50±5.10)and(50.10±5.04)grains,respectively.Compared model group with blank group,and compared experimental-L,-M,-H groups with model group,the above indicators showed statistically significant differences(P＜0.05,P＜0.01,P＜0.001).The relative expression levels of DRD2 mRNA in blank,model and experimental-L,M,H groups were 1.00±0.12,2.95±0.47,2.73±0.49,2.17±0.35 and 2.08±0.32,respectively.The relative expression levels of DRD2 mRNA in the experimental-M and experimental-H groups were significantly lower than those in the model group(all P＜0.001),with no significant difference between the two groups(P＞0.05);therefore,experimental-M was selected for subsequent experiments.The VIP levels of blank group,model group,experimental-M group,AAV9-NC group and AAV9-DRD2 group were(43.15±4.52),(64.42±7.64),(51.68±5.37),(49.25±4.44)and(56.84±6.41)ng·L-1,respectively;NO levels were(6.84±0.71),(11.68±1.37),(9.28±0.93),(9.35±0.97)and(10.45±1.03)μmol·L-1,respectively;the relative expression levels of AMPK protein were 1.00±0.15,2.42±0.34,1.68±0.17,1.55±0.18 and 1.94±0.21,respectively;the relative expression levels of eNOS protein were 1.00±0.11,3.18±0.35,2.28±0.23,2.35±0.27 and 2.95±0.33,respectively.Compared model group with blank group,compared experimental-M group with model group,and compared AAV9-DRD2 group with AAV9-NC group,the above indicators all showed statistically significant differences(all P＜0.05).Conclusion NOB can improve STC in rats,possibly by down-regulating DRD2 expression,regulating VIP and NO levels,and inhibiting the AMPK/eNOS signaling pathway.关键词
川陈皮素/慢传输型便秘/多巴胺受体D2/腺苷酸活化蛋白激酶/内皮型一氧化氮合酶/血管活性肠肽Key words
nobiletin/slow transit constipation/dopamine receptor D2/AMP-activated protein kinase/endothelial nitric oxide synthase/vasoactive intestinal peptide分类
医药卫生
