• The Journal of Korean Medicine
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• v.33 no.3
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• pp.20-32
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• 2012

Objectives: The purpose of this study was to investigate the effect of acupuncture and electro-acupuncture (EA) of low and high frequencies at Haegye (ST41) in rats. Methods: The intestinal motility of rats was experimentally suppressed with loperamide. Acupuncture, low frequency EA and high frequency EA were carried out before the loperamide administration in the pre-treatment group, and after the loperamide administration in the post-treatment group. The rats were fed charcoal and the travel rate of charcoal in the gastrointestinal track was measured to analyze the effect of acupuncture, low frequency EA and high frequency EA on the intestinal hypo-motility. Results: 1. None of acupuncture, low frequency EA or high frequency EA at ST41 showed significant influences on intestinal motility of rats in normal status. 2. Pre-treatment with acupuncture at ST41 showed no significant effect on the intestinal hypo-motility induced by loperamide in rats. 3. Pre-treatment with low frequency EA and high frequency EA at ST41 significantly reduced the suppression of intestinal motility by loperamide in rats. 4. Post-treatment of acupuncture, low frequency EA and high frequency EA at ST41 had no significant influences on the intestinal hypo-motility induced by loperamide in rats. Conclusions: These results suggest that low and high frequency EA at ST41 may be effective to prevent gastric disorders such as intestinal hypo-motility.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.1
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• pp.47-53
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• 2014

In this study, we propose that diprophylline exerts bidirectional modulation (BM) on the isolated rat jejunal segment depending on its contractile state. The results supported the hypothesis. Diprophylline ($20{\mu}M$) exerted stimulatory effects on the contractility of jejunal segment in six low contractile states while inhibitory effects in six high contractile states, showing the characteristics of BM. Diprophylline-induced stimulatory effect was significantly blocked by atropine, indicating the correlation with cholinergic activation. Diprophylline-induced inhibitory effect was partially blocked by phentolamine, propranolol, and L-N-Nitro-Arginine respectively, indicating their correlation with sympathetic activation and nitric oxide-mediated relaxing mechanisms. Diprophylline-induced BM was abolished by tetrodotoxin or in a $Ca^{2+}$ free condition or pretreated with tyrosine kinase inhibitor imatinib, suggesting that diprophylline-induced BM is $Ca^{2+}$ dependent, and that it requires the presence of enteric nervous system as well as pacemaker activity of interstitial cells of Cajal. Diprophylline significantly increased the reduced MLCK expression and myosin extent in constipation-prominent rats and significantly decreased the increased MLCK expression and myosin extent in diarrhea-prominent rats, suggesting that the change of MLCK expression may also be involved in diprophylline-induced BM on rat jejunal contractility. In summary, diprophylline-exerted BM depends on the contractile states of the jejunal segments, requires the presence of $Ca^{2+}$, enteric nervous system, pacemaker activity of interstitial cells of Cajal, and MLCK-correlated myosin phosphorylation. The results suggest the potential implication of diprophylline in relieving alternative hypo/hyper intestinal motility.