• Journal of Convergence for Information Technology
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• v.10 no.10
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• pp.109-114
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• 2020

The aim of the study was to observe the influence and related mechanism of rebamipide on the intestinal contraction. Intestinal contraction includes the activation of thick or thin filament regulation. However, there are few reports addressing the question whether this regulation is involved in rebamipide-induced regulation. We hypothesized that rebamipide plays a role in intestinal contraction evoked by carbachol in rat intestine. Interestingly, rebamipide alone didn't inhibit and rather slightly increased the contraction in the denuded muscle. Therefore, rebamipide alone and together with indomethacin increases the ileal contraction suggesting that additional pathways might be involved in the regulation of ileal contractility. In conclusion, rebamipide has some effect on the regulation of contractility and anti-ulcer by NSAIDs.

• Journal of Acupuncture Research
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• v.27 no.3
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• pp.117-126
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• 2010

Objectives : The purpose of this study was to compare the effect of needle retention(NR) and electro-acupuncture of low(EA(L)) and high(EA(H)) frequencies at Haegye($ST_{41}$) on intestinal hypermotility induced with carbachol in rats Methods : We made over-activated state of intestinal motility with carbachol in rats and caried out needle retention acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture at Haegye($ST_{41}$) or sham point in rat devided into pre-treatment group and post-treatment group. And we resulted as followings from measuring charcoal travel rate with observation of intestinal motility. Results : 1. None of acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture at $ST_{41}$ had significant influences on intestinal motility of rat in normal state. 2. Pre-treated with acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture and post-treated with acupuncture and low frequency electro-acupuncture at $ST_{41}$ didn't significantly influences intestinal motility in rat which over-activated with carbachol. 3. Post-treated with high frequency electro-acupuncture at $ST_{41}$ suppressed intestinal motility in rat which over-activated with carbachol. Conclusions : These results suggest that treatment high frequency electro-acupuncture at ST41 may be effective on gastric disorders such as intestinal hypermotility and its effect had more cure than prevention.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.135-144
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• 1988

When ginseng saponin fractions were treated with secretion regulatory agents, it increased cAMP level at the case of thyrotropin (but the amounts were small). Total saponin increased cAMP level at DEcAMP and isoproterenol, and decreased the level at carbachol and propranolol, but at NaF it had little effect. When diol saponin or triol saponin were treated with secretion regulatory agents, biol saponin decreased cAMP level but triol saponin increased it except for isoproterenol. Also, in propra%olol, which inhibits the increase of CAMP level, diol and triol saponin showed crossing effect, too. From the above results, ginseng saponin fractions are believed that it has the, effects of promotion or inhibition on cAMP production in the thyroid , both diol saponin and triol saponin have crossing effect on thyroid hormone secretion regulatory agents. The normalizatin action of ginseng saponin fractions is notable at the case of NaF and carbachol.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.2
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• pp.105-111
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• 2000

Stimulation of muscarinic receptors by carbachol (CCh) in the circular smooth muscle of the guinea pig gastric antrum causes muscle contraction. In the present study, muscarinic receptor subtype controlling the muscle contraction in response to CCh was studied using putative muscarinic receptor antagonists. Isometric force of the isolated circular muscle strips was measured in an organ bath. CCh contracted the muscle in a dose-dependent way, and each of the three muscarinic receptor antagonists, 4-diphenylacetoxy- N-methylpeperdine methiodide (4-DAMP), methoctramine and pirenzepine shifted the concentration- response curves to the right without significantly reducing the maximum force. The affinities of the muscarinic antagonists $(pA_2\;values)$ obtained from Schild plot analysis were 10.15, 7.05 and 6.84 for 4-DAMP, methoctramine and pirenzepine, respectively. These results suggest that the $M_3-subtype$ mainly mediate the muscle contraction in response to CCh in guinea pig gastric antrum.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.373-380
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• 1996

Recently we reported that GS 386, 1-(4'-methoxybenzyl)-6,7-dimethoxy-3,4-dihydroisoquinoline, inhibited amplitude of the $Ca^{2+}$ current by reducing the probability of $Ca^{2+}$ channel opening without changing channel kinetics in isolated rabbit atrial myocyte. In the present study, further investigation of the mechanism of action of GS 386 was performed using isolated rat trachealis. GS 386 concentration-dependently relaxed rat trachealis contracted by carbachol $(0.3{\mu}M)$ and high $K^+$(65.4 mM) with $IC_{50}$ 5.24 and 5.67 ${\mu}M$, respectively. Verapamil inhibited more effectively the high $K^+-contracted$ tissues than those with carbachol in the rat trachealis muscle. In $Ca^{2+}-free$ media, $Ca^{2+}-induced$ contraction was inhibited by GS 386. Furthermore, high concentration of GS 386 $(100{\mu}M)$ but not verapamil, attenuated a phasic contraction induced not only by carbachol but also caffeine, indicating that GS386 can enter into the cytoplasm where it may exert secondary actions on internal sites of the muscle, such as sarcoplasmic reticulum. Moreover, GS 386 showed verapamil-resistant component of relaxation and increased cAMP levels in rat trachal smooth muscle. These results suggest that the mechanism of action of GS 386 attributes to not only $Ca^{2+}$ antagonistic action but also weak phosphodiesterase inhibitory action.

• Journal of Acupuncture Research
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• v.26 no.2
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• pp.79-89
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• 2009

Objectives : The aim of this study was to observe the effect of acupuncture and high frequency electroacupuncture at $ST_{39}$ on intestinal motility in rats. 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 electroacupuncture at $ST_{39}$ or sham point in rat divided into pre-treatment group and post-treatment group. We fed charcoal to them after the treatment and measured the travel rate of charcoal in the gastrointestinal tract to observe intestinal motility. Results : Examining intestinal motility of normal rat treated with needle retention acupuncture at $ST_{39}$ significantly suppressed intestinal motility. Pre-treatment of needle retention acupuncture significantly suppressed intestinal motility in rat which over-activated with carbachol. Pre-treatment and post-treatment of high frequency electroacupuncture significantly suppressed intestinal motility in rat which over-activated with carbachol. All of the pre-treatment and post-treatment of needle retention acupuncture, high frequency electroacupuncture showed no significant effect than control group on intestinal motility of rat which was suppressed with loperamide. Conclusions : These results suggest that acupuncture and high frequency electroacupuncture at $ST_{39}$ have preventive and therapeutic effects on over-activated intestinal motility, and high frequency electroacupuncture is more effective.

• Korean Journal of Acupuncture
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• v.25 no.2
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• pp.179-197
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• 2008

Objectives and Methods : The purpose of this study was to observe the effects of acupuncture and electro-acupuncture (EA) at PC6 on intestinal motility in rats. We made over-activated state of intestinal motility with carbachol and suppressed state of intestinal motility with loperamide in rat, and carried out acupuncture with needle retained (NR), low frequency (2 Hz) EA and high frequency (100 Hz) EA at PC6 before or after the administration of carbachol or loperamide. The charcoal travel rate was measured to evaluate the intestinal motility. Results : 1. NR showed no significant influences on intestinal motility of rat in normal state. While, 2 Hz EA and 100 Hz EA at PC6 significantly increased the intestinal motility of rat in normal state. 2. All of the pre-treatment and post-treatment of NR, 2 Hz EA and 100 Hz EA at PC6 showed no significant effects on intestinal motility of rat which was over-activated with carbachol. 3. Both pre-treatment and post-treatment of NR significantly increased intestinal motility in rat which was suppressed with loperamide. 4. Pre-treatment of 2 Hz EA and post-treatment of 100 Hz EA significantly increased intestinal motility in rat which was suppressed with loperamide. Conclusions : These results suggest that acupuncture (NR) and EA on PC6 have preventive and therapeutic effect on suppressed intestinal motility, and NR may be more effective than EA in that condition.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.1
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• pp.19-25
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• 1997

The C-terminus ends of the second putative transmembrane domains of both $M_1$ and $M_2$ muscarinic receptors contain a triplet of amino acid residues consisting of leucine (L), tyrosine (Y) and threonine (T). This triplet is repeated as LYT-TYL in $M_1$ receptors at the interface between the second transmembrane domain and the first extracellular loop. Interestingly, however, it is repeated in a transposedfashion (LYT-LYT) in the sequence of $M_2$ receptors. In our previous work, we investigated the possible significance of this unique sequence diversity for determining the distinct differential receptor function at the two receptor subtypes. However, we found mutation of the LYTTYL sequence of $M_1$ receptors to the corresponding $M_2$ receptor LYTLYT sequence demonstrated markedly enhanced the stimulation of phosphoinositide (PI) hydrolysis by carbachol without a change in its coupling to increased cyclic AMP formation. In this work, thus, the enhanced stimulation of PI hydrolysis in the LYTLYT $M_1$ receptor mutant was further investigated. The stimulation of PI hydrolysis by carbachol was enhanced in the mutant $M_1$ receptor, and this change was not due to alterations in the rate of receptor desensitization or sequestration. The observed larger response to carbachol at mutant $M_1$ receptors was also not due to an artifact resulting from selection of CHO cells which express higher levels of G-proteins or phospholipase C. Our data suggest that although the LYTTYL sequence in $M_1$ muscarinic receptors is not involved in determining receptor pharmacology, mutation of the sequence enhanced the coupling of $M_1$ receptors to the stimulation of phospholipase C.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.5
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• pp.485-493
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• 1997

We investigated the effect of ${\alpha}-adrenergic$ and cholinergic receptor agonists on $Ca^{2+}$ current in adult rat trigeminal ganglion neurons using whole-cell patch clamp methods. The application of acetylcholine, carbachol, and oxotremorine ($50\;{\mu}M\;each$) produced a rapid and reversible reduction of the $Ca^{2+}$ current by $17{\pm}6%,\;19{\pm}3%,\;and\;18{\pm}4%$, respectively. Atropine, a muscarinic antagonist, blocked carbachol- induced $Ca^{2+}$ current inhibition to $3{\pm}1%$. Norepinephrine ($50\;{\mu}M$) reduced $Ca^{2+}$ current by $18{\pm}2%$, while clonidine ($50\;{\mu}M$), an ${\alpha}2-adrenergic$ receptor agonist, inhibited $Ca^{2+}$ current by only $4{\pm}1%$. Yohimbine, an ${\alpha}2-adrenergic$ receptor antagonist, did not block the inhibitory effect of norepinephrine on $Ca^{2+}$ current, whereas prazosin, an ${\alpha}1-adrenergic$ receptor antagonist, attenuated the inhibitory effect of norepinephrine on $Ca^{2+}$ current to $6{\pm}1%$. This pharmacology contrasts with ${\alpha}2-adrenergic$ receptor modulation of $Ca^{2+}$ channels in rat sympathetic neurons, which is sensitive to clonidine and blocked by yohimbine. Our data suggest that the modulation of voltage dependent $Ca^{2+}$ channel by norepinephrine is mediated via an α1-adrenergic receptor. Pretreatment with pertussis toxin (250 ng/ml) for 16 h greatly reduced norepinephrine- and carbachol-induced $Ca^{2+}$ current inhibition from $17{\pm}3%\;and\;18{\pm}3%\;to\;2{\pm}1%\;and\;2{\pm}1%$, respectively. These results demonstrate that norepinephrine, through an ${\alpha}1-adrenergic$ receptor, and carbachol, through a muscarinic receptor, inhibit $Ca^{2+}$ currents in adult rat trigeminal ganglion neurons via pertussis toxin sensitive GTP-binding proteins.

• Archives of Pharmacal Research
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• v.14 no.2
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• pp.181-187
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• 1991

The muscarinic antagonist 1-[benzilic 4, 4'-$[^3H]$ QUINUCLIDINYL BENZILATE $([^3H]$ QNB) bound to a single class of muscarinic receptors with high affinity in rabbit ileal membranes. The $K_D\;and\;B_{ max}$ values for $([^3H]$ QNB calculated from analysis of saturation isotherms were 52.5 pM AND 154 fmol/mg, respectively. Chlopheniramine (CHP), histamine $H_1$ blocker, increased $K_D$ vlue for $([^3H]$QNB without affecting the binding site concentrations and Hill coefficient. The $K_i$ value of CHP for inhibition of $([^3H]$QNB binding in ileal membranes was 1.44\mu{M}$ and the pseudo-Hill coefficient for CHP was close to unit. In the functional assay carbachol, muscarinic agonist, increased the contractile force of ileum with $ED_{50}$ value of $0.11\mu{M}$. CHP caused the rightward shift of the dose-response curve to carbachol. The $pA_2$ value of CHP determined from Schild analysis of carbacholinduced contraction was 5.77 and the slope was unity indicating competitive antagonism with carbachol. The dissociation constant $(K_i)$ of CHP obtained in competitive experiments with $([^3H]$ QNB was similar to the $K_A$ value (1.69 \mu{M)}$ of CHP as inhibitor of carbachol induced contraction in rabbit ileum. This result suggest that the binding of $H_i$ blocker. CHP, vs $([^3H]$QNB to muscarinic receptors in ileal membranes represents an interaction with a receptor of physiological relevance.