[Effects of tongfu decoction on rats' rapid gastric emptying].

OBJECTIVE: To observe the effects of Tongfu Decoction (TFD) on the gastric emptying of normal rats, thus exploring whether it could promote gastric emptying rapidly. METHODS: Thirty Sprague-Dawley (SD) rats were randomly divided into 3 groups, i.e., the normal control group, the domperidone group, and the TFD group, 10 in each group. They were respectively administered with normal saline, the domperidone suspension, and TFD by gastrogavage. Thirty min later the gastric emptying of mice was detected by single photon emission computed tomography technology (SPECT) labeled with 99m Tc-DTPA, and the gastric half-emptying time and the gastric emptying rate were calculated. RESULTS: The gastric half-emptying time was (19.0 +/-1.7) min in the normal control group, (12.9 +/- 3.4) min in the domperidone group, and (12.7 +/- 4.1) min in the TFD group. Compared with the normal control group, the gastric half-emptying time was significantly shortened in the domperidone group and the TFD group (P <0.05). The gastric emptying rate at 15 min was 41.1% +/- 5. 8% in the normal control group, 52.9% +/- 10.9% in the domperidone group, and 56.0% +/- 10.3% in the TFD group, while at 30 min it was 65.6% +/- 2.8%, 72.9% +/- 2.6%, and 72.4% +/- 4.9%, respectively. Compared with the normal control group, the gastric emptying rate at 15 min and 30 min both significantly increased in the domperidone group and the TFD group (P <0.05). There was no statistical difference in the gastric half-emptying time or the gastric emptying rate between the two groups (P >0.05). CONCLUSION: TFD showed similar effects as domperidone in rapidly promoting gastric emptying, and could shorten the gastric half-emptying time in normal rats.

Pyloric resection and delayed gastric liquid emptying in rats.

BACKGROUND: Surgical resection of the distal stomach impairs gastric emptying. Generally, pylorus and the antrum are removed in the distal gastrectomy, however, the pylorus is removed individually under specific circumstances. We focus on the relation between the pyloric resection and the gastric liquid emptying. AIMS: The present investigation aimed to explore the pylorectomy how to influence gastric liquid emptying in rats. METHODS: Pylorectomy and end-to-end gastroduodenal anastomosis were conducted in rats. Electrodes were implanted in the gastrointestinal serosal surface near the stoma. Total stomach, proximal stomach, distal stomach and duodenal liquid emptying, myoelectricities in the gastrointestinal tract near the stoma, and structures were examined with scintigraphy, electrode recording in vivo, and electron microscopy, respectively. RESULTS: Delayed total stomach and distal stomach emptying were found in pylorectomy rats (p<0.001). However, there was no difference in the proximal stomach and the duodenal liquid emptying compared to the controls (p>0.05). The myoelectricity of 3-5 cpm (cycles/min) in antrum and 10-12 cpm in duodenum were found in the controls and no retrograde or antegrade myoelectricities were recorded in the duodenum and antrum. High-frequency myoelectricities (tachygastria) were recorded in the antrum near the stoma (p<0.01), the retrograde and antegrade myoelectricities propagating through the stoma were recorded, and the regenerated interstitial cells of Cajal were found in stoma under electron microscope observation in pylorectomy rat. CONCLUSIONS: The gastroduodenal incoordination and abnormal myoelectricity related to impaired contraction in the antrum caused the delayed liquid gastric emptying in pylorectomy rats.

[Impact of abnormal myoelectricity at gastroduodenal anastomosis on gastric emptying in rats].

OBJECTIVE: To explore the impact of abnormal myoelectricity at gastroduodenal anastomosis on gastric emptying in rats. METHODS: Rats were randomly divided into experimental group (n=16) and control group (n=16). Pylorectomy and end-to-end gastroduodenal anastomosis were performed in the experimental group and electrodes were implanted in the serosal surface adjacent to the anastomosis. Slow waves were recorded by the implanted electrode in vivo. Gastric emptying was examined by scintigraphy. RESULTS: At the first week after surgery, antral slow-wave frequency was significantly lower in the experimental group (0.8±1.4 vs. 3.3±1.2, P<0.01), as was the duodenal slow-wave frequency (2.1±0.6 vs. 11.1±0.7, P<0.01). There was no consecutive slow-waves transduction across the pylorus or the anastomosis. Within 12-16 weeks after operation, antral slow-wave frequency in the experimental group and the control group were (8.7±0.6) cpm and (4.0±0.4) cpm, respectively (P<0.01), and duodenal slow-wave frequency were (11.1±0.8) cpm and (10.8±0.7) cpm, respectively (P>0.05). Retrograde and antegrade myoelectricity transduction through the anastomosis were detected. The mean semi-emptying time in the proximal stomach was 14.7 min in the experimental group and 13.6 min in the control group (P>0.05). Radionuclide retention rate was 25.4% in the experimental group and 39.4% in the control group (P>0.05). The mean semi-emptying time in the distal stomach was 25.3 min in the experimental group and 10.5 min in the control group (P<0.01). Radionuclide retention rate was 46.4% in the experimental group and 18.7% in the control group (P<0.01). CONCLUSION: The abnormal myoelectricity in the region of gastroduodenal stoma may delay liquid gastric emptying in pylorectomy rats.