• Korean Journal of Veterinary Research
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• v.39 no.6
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• pp.1073-1080
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• 1999

Previous studies suggested that the inhibition of thyroxine ($T_4$) release by ${\alpha}_1$-adrenoceptor and muscarinic receptor stimulation results in activated protein kinase C (PKC) from mouse and guinea pig thyroids. In the present study, the effect of carbachol, methoxamine, phorbol myristate acetate (PMA), and R59022 on the release of $T_4$ from the mouse, rat, and guinea pig thyroids was compared to clarify the role of PKC in the regulation of the release of $T_4$. The thyroids were incubated in the medium containing the test agents, samples of the medium were assayed for $T_4$ by EIA kits. Forskolin, an adenylate cyclase activator, chlorophenylthio-cAMP sodium, a membrane permeable analog of cAMP, and isobutyl-methylxanthine, a phosphodiesterase inhibitor, like TSH (thyroid stimulating hormone), enhaced the release of $T_4$ from the mouse, rat, and guinea pig thyroids. Methoxamine, an ${\alpha}_1$-adrenoceptor agonist, inhibited the TSH-stimulated release of $T_4$ in mouse, but not rat and guinea pig thyroids. In contrast, carbachol, a muscarinic receptor agonist, inhibited the release of $T_4$ in guinea pig, but not mouse and rat thyroids. These inhibition were reversed by prazosin, an ${\alpha}_1$-adrenoceptor antagonist or atropine, a muscarinic antagonist or $M_1$- and $M_3$-muscarinic antagonists, in mouse or guinea pig thyroids. In addition, staurosporine, a PKC inhibitor, reversed methoxamine or carbachol inhibition of TSH stimulation. Furthermore, PMA, a PKC activator, and R59022, a diacylglycerol (DAG) kinase inhibitor, inhibited the TSH-stimulated release of $T_4$ in mouse, rat, and guinea pig thyroids. These inhibition were blocked by staurosporine. These findings suggest that the activation of receptor or DAG inhibits TSH-stimulated $T_4$ release through a PKC-dependent mechanism in thyroid gland.

• Journal of Acupuncture Research
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• v.25 no.4
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• pp.59-69
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• 2008

Objectives : The purpose of this study was to observe the effects of acupuncture and electro-acupuncture(EA) at $LI_{11}$ on intestinal motility in rats. Methods : We made over-activated and suppressed state of intestinal motility with carbachol and loperamide in rat and carried out acupuncture with needle retained(NR), low frequency(2 Hz) EA and high frequency(100Hz) EA at $LI_{11}$ before or after the administration of carbachol or loperamide. The charcoal travel rate was measured to evaluate the intestinal motility. Results : 1. NR, 2Hz EA and 100Hz EA at $LI_{11}$ showed no significant influences on intestinal motility of rat in normal state. 2. All of the pre-treatment and post-treatment of NR, 2Hz EA and 100Hz EA at $LI_{11}$ showed no significant effects than control group on intestinal motility of rat which was over-activated with carbachol. 3. The pre-treatment of 2Hz EA and 100Hz EA at $LI_{11}$ on intestinal motility of rat which was suppressed with loperamide showed no significant influences but in the L-$LI_{11}$-EA(L) and L-$LI_{11}$-EA(H) groups, intestinal motility was significantly increased than L-control group. Conclusions : These results suggest that acupuncture and EA on $LI_{11}$ have preventive effect and therapeutic effect on suppressed intestinal motility, and EA is more effective than NR.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.639-645
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• 1997

The purpose of the present study is to determine the role of muscarinic cholinergic receptors of posterior hypothalamus in the central blood pressure regulation when respiration is controlled. In anesthetized and artificially ventilated rats, vasodepressor response was evoked by injection of L-glutamate(10 nmol) neuroexcitatory amino acid into the posterior hypothalamic area. The injection of $carbachol(0.5{\sim}8\;nmol)$ into the same area induced dose-dependent vasodepressor and bradycardic responses. Pretreatment with atropine(4 nmol) completely blocked the vasodepressor response to carbachol(2 nmol). In contrast, in spontaneously breathing rats, the injection of carbachol(8 nmol) into the posterior hypothalamic area induced the vasopressor and tachycardic responses. These results suggest that the muscarinic cholinergic receptors in the posterior hypothalamic area primarily play an inhibitory role in the central regulation of blood pressure and heart rate.

• The Korean Journal of Physiology
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• v.26 no.2
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• pp.137-141
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• 1992

The present study was aimed at elucidating the mode of inhibitory action of tricyclic antidepressants on the smooth muscle. Effects of amitriptyline on the isolated detrusor muscle strips of the urinary bladder of the rabbit were examined. The spontaneous rhythmic movement of the muscle preparation was frequently observed, which was decreased or abolished by addition of amitriptyline $(10^{-5}{\sim}10^{-3}\;M)$. The muscle preparation responded with contraction dose dependently to carbachol, of which dose response curve shifted to the right in the presence of either amitriptyline or atropine. However, amitriptyline produced a nonparallel shift, whereas atropine caused a parallel one. In calcium free medium, the contraction response to carbachol was markedly decreased, which was resumed by the addition of $CaCl_2$ (2.5mM), but not in the presence of either amitriptyline or nifedipine. KCI (60 mM) produced a potent contraction, which was abolished in the presence of amitriptyline or nifedipine. These results suggest that amitriptyline, unlike atropine, not only acts as a noncompetitive antagonist at cholinergic muscarine receptors but also inhibits Ca-influx through the muscle cell membrane.

• The Journal of Korean Medicine
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• v.30 no.6
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• pp.9-16
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• 2009

Objectives: To clarify the effects of Jungri-tang Gamibang on accelerating small intestinal movement induced by the stimulation of cholinergic neurotransmission. Methods: 500, 250 and 125mg Jungri-Tang Gamibang or 20mg domperidone were dissolved or suspended in distilled water and orally pretreated on the carbachol-accelerated small intestinal transit mice once a day for 7 days at a volume of 10ml/kg (of body weight) using a Zonde needle attached to 1 ml syringes containing test drugs. Result: Significantly (p<0.01) increase of % regions of activated charcoal transit in the small intestine was detected in carbachol control compared to that of intact control. However, significant (p<0.01) decreases of % regions of activated charcoal transit were dose-dependently observed in all Jungri-Tang Gamibang extracts or domperidone-pretreated groups. Conclusions: it was concluded that Jungri-tang Gamibang enhancement in the normal intestinal motility and normalization in the accelerated intestinal motility might interfere with a variety of muscarinic, adrenergic and histaminic receptor activities or with the mobilization of calcium ions required for smooth muscle contraction non-specifically.

• Molecules and Cells
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• v.22 no.1
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• pp.65-69
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• 2006

In murine gastrointestinal myocytes muscarinic stimulation activates nonselective cation channels via a G-protein and $Ca^{2+}$-dependent pathway. We recorded inward cationic currents following application of carbachol ($I_{CCh}$) to murine gastric myocytes held at -60 mV, using the whole-cell patch-clamp method. The properties of the inward cationic currents were similar to those of the nonselective cation channels activated by muscarinic stimulation in other gastrointestinal smooth muscle cells. CCh-induced $I_{CCh}$ and spontaneous decay of $I_{CCh}$ (desensitization of $I_{CCh}$) occurred. Unlike the situation in guinea pig gastric myocytes, desensitization was not affected by varying $[EGTA]_i$. Pretreatment with the PLC inhibitor (U73122) blocked the activation of $I_{CCh}$, and desensitization of $I_{CCh}$ was attenuated in PLC ${\beta}_1$ knock-out mice. These results suggest that the desensitization of $I_{CCh}$ in murine gastric myocytes is not due to a pathway dependent on intracellular $Ca^{2+}$ but to the PLC ${\beta}_1$ pathway.

• Journal of Acupuncture Research
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• v.25 no.5
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• pp.27-42
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• 2008

Objectives : The purpose of this study was to observe the effects of acupuncture and electro-acupuncture at $LR_3$ on intestinal motility in rat. Methods : We made over-activated state of intestinal motility with carbachol and suppressed state of intestinal motility with loperamide in rat and carried out needle retention acupuncture and high frequency electro-acupuncture at $LR_3$ in rat devided into pre-treatment group and post-treatment group. The charcoal travel rate was measured to evaluate the intestinal motility. Results : 1. High frequency electro-acupuncture at $LR_3$ have significant influences on intestinal motility of rat in normal state. 2. Pre-treatment of needle retention acupuncture, high frequency electro-acupuncture significantly decreased intestinal motility in rat which over-activated with carbachol. 3. Post-treatment of high frequency electro-acupuncture significantly increased intestinal motility in rat which suppressed with loperamide. Conclusions : These results suggest that acupuncture and electro-acupuncture at $LR_3$ are effective on intestinal motility in rat.

• Journal of Life Science
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• v.25 no.10
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• pp.1103-1109
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• 2015

Cholinergic innervation of the hippocampus is known to be correlated with learning and memory. The cholinergic agonist carbachol (CCh) modulate synaptic plasticity and produced long-term synaptic depression (LTD) in the hippocampus. However, the exact mechanisms by which the cholinergic system modifies synaptic functions in the hippocampus have yet to be determined. This study introduces an acetylcholine receptor-mediated LTD that requires internalization of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors on the postsynaptic surface and their intracellular mechanism in the hippocampus. In the present study, we showed that the application of the cholinergic agonist CCh reduced the surface expression of GluA2 on synapses and that this reduction was prevented by the M1 muscarinic acetylcholine receptor antagonist pirenzepine in primary hippocampal neurons. The interaction between GluA2 and the glutamate receptor-interacting protein 1 (GRIP1) was disrupted in a hippocampal slice from a rat upon CCh simulation. Under the same conditions, the binding of GluA2 to adaptin-α, a protein involved in clathrin-mediated endocytosis, was enhanced. The current data suggest that the activation of LTD, mediated by the acetylcholine receptor, requires the internalization of the GluA2 subunits of AMPA receptors and that this may be controlled by the disruption of GRIP1 in the PDZ ligand domain of GluA2. Therefore, we can hypothesize that one mechanism underlying the LTD mediated by the M1 mAChR is the internalization of the GluA2 AMPAR subunits from the plasma membrane in the hippocampal cholinergic system.

• Current Research on Agriculture and Life Sciences
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• v.10
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• pp.19-33
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• 1992

This paper was investigated to know that the effect and mode of action of essential oil of Acorus calamus L. and Acours gramineus Soland on motility of isolated rabbit jejunum segment. The results were as follows : 1. Both essential oil of Acorus calamus L. and Acorus gramineus Soland were showed relaxant effect on motility of isolated rabbit jejunum segment and this relaxant effect was augmentated in proportion to increase of concentration of essential oil. 2. ED 50 of essential oil of Acorus calamus L. and Acorus gramineus Soland were 0.0045%, 0.0035%, respectively. 3. The relaxed rabbit jejunum segments by eseential oil of Acorus calamus L. and Acorus gramineus Soland were recovered by carbachol, pilocarpine, and barium chloride but partially recovered by histamine. 4. The contracted rabbit jejunum segmants by carbachol, pilocarpine, histamine and barium chloride were relaxed by essential oil of Acorus calamus L. and Acorus gramineus Soland. In conclusion, it is thought that essential oil of Acorus calamus L. and Acorus gramineus Soland were relaxed the motility of isolated rabbit jejunum segment by neurotropic and musculotropic action.

• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.13-22
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• 1989

To investigate the effect of diazepam on the contractility of the intestinal smooth muscle, longitudinal muscle strip isolated from rat ileum was prepared for myography in isolated organ bath. 1) Basal tone of ileal muscle was reduced by diazepam concentration-dependently. 2) Higher concentrations(30 and 100 microM) of diazepam inhibited(p<0.05, p<0.001) the carbachol-induced contraction in a concentration-dependent manner ; but lower concentration of diazepam(10 microM) enhanced(p<0.05). 3) Histamine-induced contraction was inhibited by pretreatment with diazepam in a concentration-dependent manner. 4) $Ca^{++}$-induced tension recovery in calcium-free solution was inhibited in the presence of diazepam concentration-dependently. These results suggest diazepam reduces the contractility of the longitudinal muscle isolated from rat ileum via interference with influx of calcium into the muscle cells.