Effect of L-cysteine on colonic motility and the underlying mechanism / 生理学报

The purpose of the present study is to investigate the effect of L-cysteine on colonic motility and the underlying mechanism. Immunohistochemical staining and Western blot were used to detect the localization of the HS-generating enzymes cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE). Organ bath system was used to observe the muscle contractile activities. Whole-cell patch-clamp technique was applied to record ionic channels currents in colonic smooth muscle cells. The results showed that both CBS and CSE were localized in mucosa, longitudinal and circular muscle and enteric neurons. L-cysteine had a dual effect on colonic contraction, and the excitatory effect was blocked by pretreatment with CBS inhibitor aminooxyacetate acid (AOAA) and CSE inhibitor propargylglycine (PAG); L-cysteine concentration-dependently inhibited L-type calcium channel current (I) without changing the characteristic of L-type calcium channel (P < 0.01); In contrast, the exogenous HS donor NaHS increased I at concentration of 100 μmol/L, but inhibited I and modified the channel characteristics at concentration of 300 μmol/L (P < 0.05); Furthermore, L-cysteine had no effect on large conductance calcium channel current (I), but NaHS significantly inhibited I (P < 0.05). These results suggest that L-cysteine has a potential dual effect on colonic smooth muscle and the inhibitory effect might be directly mediated by L-type calcium channel while the excitatory effect might be mediated by endogenous HS.

Effects of serum containing Chinese medicine Sanpi Pingwei () formula on proliferation and apoptosis of human SGC-7901 cells / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of serum containing Chinese medicine (CM) Sanpi Pingwei (, SPPW) formula on the proliferation and apoptosis of human SGC-7901 cells and the possible mechanism.</p><p><b>METHODS</b>Serum containing CM SPPW formula (SPPW serum) was prepared by a serum pharmacology method. Human SGC-7901 cells were incubated with SPPW serum at three different concentrations and with the anticancer drug 5-fluorouracil (5-FU), respectively. Cell proliferation was assessed by MTT assay, and cell apoptosis was detected by flow cytometry assay. Real-time quantitative polymerase chain reaction (RT-PCR) and Western blot assay were employed to confirm the expressions of Bcl-2, Bax and p53 in SGC-7901 cells at mRNA and protein levels, respectively.</p><p><b>RESULTS</b>SPPW serum suppressed the proliferation of SGC-7901 cells in a time- and dose-dependent manner. The colony forming rate of negative control was 48.2%, while those in the three SPPW serum groups and the 5-FU group decreased significantly (P<0.01). The number of colony forming units in the SPPW high dosage group was significantly smaller than that in the 5-FU group (P<0.01). MTT assay showed that SPPW serum restrained the proliferation of SGC-7901 cells, and the inhibition rate increased significantly in a dose-dependent manner. Annexin V/PI Assay suggested that SPPW serum induced the apoptosis of SGC-7901 cells significantly. RT-PCR and western blot assay indicated that SPPW serum upregulated the protein and mRNA expression levels of Bax and p53 in SGC-7901 cells, but downregulated the protein and mRNA expressions of Bcl-2.</p><p><b>CONCLUSIONS</b>SPPW formula inhibits the proliferation of SGC-7901 cells in vitro and induces the cell apoptosis. It plays an anticancer role by regulating the expressions of Bax, p53 and Bcl-2 in SGC-7901 cells.</p>

Effect of ghrelin on duodenal myoelectric activity in conscious rats / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of ghrelin on the duodenal myoelectrical activity during the feeding state and the fasting state in rats.@*METHODS@#One pair of bipolar silver electrodes were chronically implanted in the duodenal serosa of rats for electromyography. The myoelectrical activity was recorded when ghrelin was injected intravenously into rats during the feeding state or the fasting state. Some rats were pretreated with atropine, phentolamine, propranolol, L-arginine, and (D-Lys3)GHRP-6 respectively to explore the mechanism of ghrelin.@*RESULTS@#Duodenal migrating myoelectrical complex (MMC) could be induced by ghrelin in the feeding state. Ghrelin could shorten the length of duodenal MMC cycle and increase the amplitude and frequency of phase III during the fasting state. The percentage of phase III in the MMC cycle did not change. These effects were inhibited by atropine and L-arginine (D-Lys3)GHRP-6, but not by propranolol and phentolamine.@*CONCLUSION@#Ghrelin seems to be closely related to the duodenal motility. The excitatory effect of ghrelin on duodenal MMC might rely on the cholinergic pathway, and have a close relationship with NO. The receptor of ghrelin can regulate its activity.

Effect of Mexican tea herb and pilular adina herb on concrescence of gastric mucosa in experimental gastric ulcer rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To study the effect and mechanism of mexican tea herb and pilular adina herb (abbreviated to MP) on concrescence of gastric mucosa in experimental gastric ulcer rats by observing the changes of epidermal growth factor (EGF), nitrogen monoxidum (NO) and expression of epidermal growth factor receptor (EGFR).</p><p><b>METHODS</b>The rat ulcer model was established by 100% glacial acetic injection into the subserosa. The ulcer index (UI) was measured by sliding caliper. The levels of NO and EGF in tissue and serum were measured by the nitrate reductase method and enzyme-linked immunosorbent assay, respectively. The expression of EGFR in the mucosa around the ulcer was detected by the immunohistochemical assay and microimage analysis system.</p><p><b>RESULTS</b>(1) Compared with the model group, UI of MP groups (10, 15 and 20 mg.kg(-1).d(-1)) and ranitidine group was lower (P<0.05 or P<0.01), the levels of NO and EGF in the tissue and serum were higher (P<0.05), the thickness of regenerated mucous membrane increased, and the width loss of lamina muscularis mucosa decreased (all P<0.05). (2) The expression of EGFR is weakly positive in gastric mucosa cells in the normal group, mainly in the cytoplasm and cytomembrane. In the model group, the expression of EGFR was mainly in epithelial cells in cervical part and basilar part of gastric gland around the ulcer margin, and the number of cells with EGFR weakly positive expression was more than that in the normal group. Compared with that in the normal and model groups, the number of cells with EGFR positive in MP groups and ranitidine group increased (all P<0.05), with weakly positive expression.</p><p><b>CONCLUSION</b>MP can protect gastric mucosa, cure gastric ulcer, restrain the secretion of gastric acid, and boost multiplication, differentiation, migration and repair of the endothelial cell by promoting the secretion of NO and EGF, and increasing the expression of EGFR of gastric mucosa epithelial cells.</p>

Investigation on the health-related quality of life among 411 patients with irritable bowel syndrome / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate and compare the health-related quality of life (HRQOL) on patients with irritable bowel syndrome (IBS).</p><p><b>METHODS</b>Following the Rome III Criteria, 411 IBS patients and 430 healthy people were selected as subjects,who were outpatients in Department of Gastroenterology, 2nd Hospital of Xi' an Jiaotong University and Shaanxi Provincial People's Hospital from July 2006 to April 2007. Using the 36-Item Short-Form Health Survey (SF-36). This study compared the SF-36 scale scores of IBS patients with the healthy people.</p><p><b>RESULTS</b>On all of the 8 SF-36 scales, patients with IBS scored significantly lower than healthy people (P < 0.001). Decrements in HRQOL were most predominant in general health perception and role limitations caused by emotional health problem, with scores of 33.5 + 16.9, 40.8 +/- 25.1 respectively. The emotional well-being and energy/fatigue scale scores were also quite low (42.2 +/- 19.3,43.1 +/- 20.2,respectively). They also scored significantly lower on both physical summary. and mental summary scores (P < 0.001). IBS patients were classified into IBS with constipation,IBS with diarrhea, mixed IBS and unsubtyped IBS subgroups, with percentages as 25.3%, 50.1%, 11.2% and 13.4% respectively.</p><p><b>CONCLUSION</b>IBS patients experienced great impairment in HRQOL. These data offered further insight into the impact of IBS on patient functional status and well-being.</p>

Expression and role of 5-HT7 receptor in brain and intestine in rats with irritable bowel syndrome / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The 5-hydroxytryptamine7 receptor (5-HT(7) receptor, 5-HT(7)R) plays an important role in the regulation of smooth muscle relaxation and visceral sensation and might be involved in the pathogenesis of the gastrointestinal dyskinesia, abdominal pain and visceral paresthesia in irritable bowel syndrome (IBS). The aim of this study was to investigate the role of the 5-HT(7) receptor in the pathogenesis of IBS.</p><p><b>METHODS</b>A rat model of irritable bowel syndrome with diarrhea (IBS-D) was established by colonic instillation of acetic acid and restraint stress. A rat model with irritable bowel syndrome with constipation (IBS-C) was established by stomach irrigated with 0 - 4 degrees C cool water daily for 14 days. The content and distribution of 5-HT in the brain and gut were examined by immunohistochemistry and the mRNA expression of the 5-HT(7) receptor was determined by fluorescent quantitative reverse transcription polymerase chain reaction. The accumulation of cyclic adenosine monophosphate (cAMP) in all the same tissues was measured by radioimmunity.</p><p><b>RESULTS</b>The models of IBS were reliable by identification. The immunohistochemistry results showed that there were significantly more 5-HT positive cells in the IBS-D group than in the control group in the hippocampus, hypothalamus, jejunum, ileum, proximate colon and distal colon (P < 0.05), as well as more than were found in the IBS-C group in jejunum and ileum (P < 0.05). There were more 5-HT positive cells in the IBS-C group than in the control hippocampus, hypothalamus, ileum, proximate colon, and distal colon (P < 0.05). Real time-PCR results showed that the expression level of the 5-HT(7) receptor in both the IBS-C and IBS-D groups were enhanced compared with the control group in the hippocampus and hypothalamus (P < 0.05). The expression level of 5-HT(7) receptors in the IBS-C group was notably greater when compared with the controls in the ileum and colon (P < 0.05). The cAMP accumulation in the hippocampus and hypothalamus in both the IBS-C and IBS-D groups was higher than that in the control group (P < 0.01 and P < 0.05). The cAMP accumulation in the IBS-C group was higher than that in the control group in the proximal and distal colon (P < 0.05).</p><p><b>CONCLUSIONS</b>The increased 5-HT content in the brain and intestine is related to the IBS pathogenesis. The up-regulated expression of the 5-HT(7) receptor in the brain and colon might play an important role in the pathogenesis of IBS-C.</p>