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Objective To investigate the expression of estrogen receptor in gastric antrum and the effect of estrogen on electrical activity of gastric antrum smooth muscle in female rabbits in virtue of the constructed mathematical model in order to explore the regulation of estrogen on gastric motility. Methods Using immunofluorescence to observe the expression of estrogen receptor in gastric antrum. Using BL-420F bio monitor to monitor: Comparing the difference of antral electromyography index between rabbits in ovariectomized group and rabbits in sham operating group; Observing the dose-response relationship between doses of estradiol (0,0. 1,0. 15,0. 2,0. 25 and 0. 3 mg/ kg). To construct the mathematical model, and to analyze the dose-response relationship and mechanism of action. Rresult The expression of estrogen receptor in the antral wall of the stomach was negative. The activity index of gastric antrum myoelectric activity was significantly decreased after ovarian ablation (P<0. 01). With the increase of estradiol dose, the activity index of gastric antrum muscle increased and then decreased. Analysis of variance showed that the difference of antral electromyographic activity index between adjacent groups was significant (P<0. 05) or extremely significant (P<0. 01). Taking the estradiol dose as the independent variable x, the antral electromyography activity index was the dependent variable y, and the fitting wass obtained: y= 2. 80 + 5. 65 × exp{ -0. 5 × [(x-0. 159) / 0. 038 ]
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Objective: To establish a mathematical model of the injection by dorsal motor nucleus of vagus (DMV), the dose of L-glutamic acid (L-Glu) and the duodenal myoelectric activity index of female rabbits was established to provide a theoretical basis for studying the mechanism of action of hormones, cytokines and other vagal activity. Methods: In this experiment, we used microinjection technique to inject L-Glu to DMV by doses of 0 mol/L, 0.05 mol/L, 0.10 mol/L, 0.15 mol/L and 0.20 mol/L, monitoring the duodenal myoelectric activity of ovarian abducted rabbits, the number of samples per dose group was 5, and construct a mathematical model between the dose of L-Glu and the index of duodenal myoelectric activity. Results: After t-test analysis, the amplitude of myoelectric activity increased gradually between adjacent dose groups, and the difference was extremely significant (P < 0.01). The frequency was gradually strengthened, and the difference between 0 mol/L and 0.05 mol/L, 0.10 mol/L and 0.15 mol/L was significant (P < 0.05). The index of myoelectric activity increased gradually, and the difference between groups was extremely significant (P<0.01). With L-Glu concentration as the independent variable x, the duodenal myoelectric activity index was the dependent variable y, the constructor relationship was y= 13.71/1 + exp [-22.35 x (x-0.082)], function fitting accuracy was R =0.9948, P<0.01.belonging to growth type S logic function. Function analysis showed that the L-Glu dose of 0.082 mol/L was the inflection point of the logic function. As the dose range of L-Glu was 0 mol/L-0.082 mol/L, duodenal myoelectric activity index showed an exponential growth pattern, as the L-Glu dose was greater than 0.082 mol/L, the duodenal myoelectric activity index showed a logarithmic growth pattern with a theoretical limit of 13.71. Conclusion: L-Glu has a significant dose-effect relationship on the promotion of duodenal myoelectric activity in rabbits by DMV, and have the effect of interval, the mathematical model laid the theoretical foundation for further research on the role of hormones and cytokines on this basis.
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Objective To investigate the role of motility of Oddi's sphincter in pigment gallbladder stone formation in the model of guinea pigs.Methods Thirty-four general adult male Hartley guinea pigs were divided randomly into two groups.Control group (10 guinea pigs)and pigment stone groups (24 guinea pigs,which were divided into 4 subgroups with 6 guinea pigs each according to the time they were sacrificed),fed with pigment lithogenic diet.After 3,6,9 and 12 weeks later,Oddi's sphincter manometry and myoelectric activity record were obtained by multifunctional physiograph at each stage.Results The incidence of pigment gallstone formation was 0,0,16.7％ and 66.7％ in 3w,6w,9w and 12w group,respectively.The frequency of myoelectric activity decreased apparently in the 3w group(P ＜ 0.05).The amplitude of myoelectric activity had the tendency of decreasing but not statistically significant.The motility frequency of Oddi's sphincter decreased greatly in the 9w group (P ＜ 0.05).The basal pressure of Oddi's sphincter and common bile duct increased markedly in the 12w group [from (25 ± 8) mmHg (1 mmHg =0.133 kPa) to (41 ± 12) mmHg and from (22 ± 8) mmHg to (39 ± 12) mmHg,P ＜ 0.05)].Conclusions Pigment lithogenic diet may induce dysfunction of Oddi's sphincter.The disturbance of Oddi's sphincter motility may play a role in pigment gallstone formation.
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Objective To investigate the effects of hypercholesteremia on the motor function of sphincter of Oddi (SO). Methods Thirty-two rabbits were divided into control group and experimental groups. In the control group, the rabbits were fed with normal diet. In the experimental groups, the rabbits were fed with normal diet + cholesterol for 4, 6 and 10 weeks. Myoelectric activity and pressures of SO were detected. All data were analyzed by t test. Results The serum total cholesterol and low density lipoprotein cholesterol were at a high level in rabbits which were fed with normal diet + cholesterol for 10 weeks (t=9.63, 11.38, P <0.05); basal pressure, pike pressure and amplitude of SO were significantly elevated (t=5.23, 6.34, 3.24, P < 0.05) ; the spike potential of SO changed to myoelectronic activity, with prolonged time period of myoelectronic activity, while the discharge rate was decreased (t=13.68, 10.18, P < 0.05). Conclusion Hypercholesteremia may change the motor function of SO and enhance its peristalsis to speed up the excretion of bile.
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s Objective To study the pathogenesis of slow transit constipation by investigating the changes in colonic myoelectric activity in rats with slow transit constipation. Methods A rat model of slow transit constipation was replicated and the colonic myoelectric activity was recorded. Results Compared with normal rats, the frequency of myoelectric activity in a part of rats in the model group was seen to be decreased (5.55?1.20/min,P
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Objective To discuss application value of intestinal electromyography in patients with hepatic cirrhosis and to observe intestinal myoeletric activity.Methods There were 65 cases of hepatic cirrhosis in expermental group and 30 cases in control group. All the cases were recorded body surface intestinal electromyography using gastrointestinal myoelectric analyzer(WCDF-4B, Hefei , P.R.China). The parameters included average peak range-Ap, main frequency-Fp, average over zero frequency-Fz and special wave form were surveyed.Results Sharp higher Fz abnormal rate and emergence rate of special wave form in hepatic cirrhosis group were higher than in control group,P0 05.Conclusions In hepatic cirrhosis group,Fz was much higher than that in control group. And the intestinal myoelectric activity increased in the patients with hepatic cirrhosis,which represented by appearance of characteristic wave form that was frequent micromigration wave as well as load wave. Those changes accounted for heighten and irregularity of excitability intestinal myoelectric activity. Moreover, it will increase for the incidence of abnormality of intestinal myoelectric activity along with damage degree of hepatic function. Intestinal electromyography is a reliable method to judge intestinal myoelectric activity, the method has characteristics of harmless,free pain, convenient, safty and steady.
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Objective To investigate the distribution of interstitial Cajal-like cells(ICLC) in ampulla and the myoelectric activities of the sphincter of Oddi(SO) of adult guinea-pigs.Methods C-Kit immunohistochemical staining was carried out on whole-mount preparations of guinea-pigs' ampulla region.The myoelectric activities of SO were recorded by using the contact electrode on mucosa.Result C-Kit-positive ICLC were observed in both exterior and inner wall of ampulla.Some of these cells were distributed in the circular and longitudinal smooth muscle cell(SMC) layers assuming a spindle-like shape.Another sub-group of ICLC,which were located between the longitudinal and circular SMC layers,were shown to have oval or triangle cell bodies with projection of more than three long processes.These cells interlaced into a cellular network,closely resembling the interstitial cells of Cajal(ICCs),around the myenteric nervous plexus(ICC-MY) in the duodenum.At the inner side of circular SMC layer of the exterior wall,ICLC were similar to ICCs associated with the deep muscular plexus(ICC-DMP) of small intestine.In the inner wall of the ampulla,a large amount of ICLC were found in the SMC layers or bundles,running parallel with them.At the opening of the ampulla,a number of ICLC surrounded the opening to form a ring.The spontaneous rhythmic myoelectric activities could be recorded in the SO.Conclusion It is suggested that the ICLC might contribute to the regulation of the spontaneous rhythmic contraction,and it might be related to development of motility disorders of the SO.
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Objective:To observe the effects of Rhizoma coptidis decoction on the myoelectric activity of womb of virginal rats and to discuss its mechanism. Methods: The changes of uterine myoelectric activity of rats were recorded by Biolap 98 biological system with a pair of mini bipolar Ag AgCl electrodes implanted on the uterine serosal surface. Rhizoma coptidis decoction was injected to find their effects on uterine myoelectric activity of rats, then M, H 1,?,L calaium channel and prostaglandin synthetase were blocked or inhibited respectively to be observed their influence Rhizoma coptidis decoction. Results:Rhizoma coptidis decoction can significantly increase uterine myoelectric activity of rats. After M and H 1 receptors were blocked, the effects of Rhizoma coptidis decoction were partially decreased. The effects of Rhizoma coptidis decoction were disappeared with L calcium channels blocked. But, nothing happened if ? receptor was blocked or prostaglandin synthetase was inhibited. Conclusions: Rhizoma coptidis decoction can significantly increase uterine myoelectric activity of rats, which may be associated with M receptor, H receptor and L calcium channels, nothing with ? receptor and synthesis or releasing of prostaglandin.