• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.207-215
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• 1989

The authors studied ED50 of bethanechol on the contractilities of the smooth muscles isolated from various organs of rat under the presence of atropine(a classical competitive blocker of cholinergic muscarinic receptor) or minaprine(a newly developed antidepressant drug) to investigate the pheripheral anticholinergic effect of minaprine. The results were as follows ; 1) There was no significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine $10^{-8}M$ and $10^{-7}M$ in the smooth muscles isolated from the duodenum. 2) There was no significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine $10^{-8}M$ and $10^{-7}M$ in the smooth muscles isolated from the ascending colon. 3) There was significant difference between ED50 of bethanechol in the control group and that under the presence of minaprine $10^{-8}M$ and $10^{-7}M$ in the smooth muscles isolated from the urinary bladder(P<0.01). 4) There was significant difference between ED50 of the atropine $10^{-8}M$ and minaprine ($10^{-8}M$) in the smooth muscles isolated from the urinary bladder(P<0.05).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.4
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• pp.340-349
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• 2007

Free flap transplantation with microvascular anastomosis has been successfully performed by development of surgical technique, materials and postoperative monitoring equipments of flap. But success rate of microvascular anastomosis is influenced by various factors, and failure rate is about 5-10%. The most influential factor for success rate is surgical technique and other factors that influence failure of microvascular anastomosis are ischemic time of free flap, thrombus formation of anastomosis region and vascular spasm. In this study, vascular patency and thrombus formation in experimental micro-venous anastomosis, and endothelial repair were observed with histologic analysis, scanning electron microscopy, transmission electron microscopic examination. The results were obtained as follows: 1. In vascular patency test in 30 minute and 7 days after micro-venous anastomosis with heparin irrigation, all of 12 anastomosis site were good vascular patency. 2. In thrombus formation in 2 weeks group(Experimental I), 2 site of 6 cases were observed thrombus, and in 4 weeks group(Experimental II), 1 site of 6 cases were observed thrombus. 3. In histologic examination, normal vein(Control Group) showed continued internal elastic lamina, well formed thick smooth muscle layer and connective tissue. The group of 2 weeks after microvenous anastomosis(Experimental I) showd locally recovered internal lamina, discontinued internal lamina, disorganized smooth muscle cells and granulation tissue around suture silk. In the group of 4 weeks after micro-venous anastomosis(Experimental II), anastomosis site showed almostly continued internal lamina, disorganized smooth muscle cells and cicartrized tissue around suture silk. 4. In scanning electron microscope examination in 2 weeks(Experimental I) after micro-venous anastomosis, mesh fibrin formation showed near to endothelial cells, and in 4 weeks after micro-venous anastomosis(EXperimental II), numerous blood cells and fibrin mesh formation was seen associated with irregular endothelial cell arrangement. 5. In transmission electron microscope examination in 2 weeks after micro-venous anastomosis(Experimental I), irregular arrangement of smooth muscle cells was seen adjacent to collagenized tissue around suture silk. In 4 weeks after micro-venous anastomosis(Experimental II), denuded venous wall composed of relatively well arranged smooth muscle cells was covered by endothelial cells, but fibroblast cells and foreign body giant cells near to suture silk was remained. From the results obtained in this study, results of good vascular patiency and anti-thrombotic effect of heparin were obtained as a local irrigation solution, and repair of venous endothelial cell was observed in 2 weeks after micro-venous anastomosis.

• Therapeutic Science for Rehabilitation
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• v.5 no.2
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• pp.81-92
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• 2016

Objective: This study aim is to identify whether 30minutes optokinetic stimulation(OKS) with smooth pursuit eye movement can alleviate chronic hemispatial neglect. Methods: We applied optokinetic stimulation with smooth pursuit eye movement to 2 chronic hemispatial neglect patients. experimental duration was total 4weeks - 1week baseline, 2weeks OKS intervention, 1week 2nd. baseline. The intervention was 10 OKS sessions (30min each, 1session daily, from Monday to Friday) over a period of 2weeks. The neglect test carried out 3 times a week every other day. The OKS was provided on the screen when patient sat in front of the screen(13.5 inch). The OKS video that the 24 yellow squares moving coherently from the right to the left side. Patients were instructed to perform smooth pursuit eye movement without head and neck movement. Results: As a result of the OKS for 2weeks, the degree of neglect trends to decrease on both 2 cases compared to baseline A. The degree of the neglect of subject 1 tended to increase the at the baseline A. In contrast, the subject 2 showed that tendency that the degree of the neglect declined additionally at the baseline A. Conclusions: We identified that 30 minutes optokinetic stimulation with sooth pursuit eye movement is effective intervention method for chronic hemispatial neglect.

• Journal of Chest Surgery
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• v.40 no.4 s.273
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• pp.256-263
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• 2007

Background: Intimal hyperpiasia is characterized by a proliferation of vascular smooth muscle cells in the intimal layer Epigallocatechin-3-gallate (EGCG) is known to suppress smooth muscle cell proliferation. We propose that EGCG may have a protective effect against the development of intimal hyperplasia through the suppression of smooth muscle cell proliferation. Material and Method: Human umbilical vein endothelial cells (HUVEC) and rat aortic smooth muscle cells (RASMC) were cultured with different concentrations of EGCG, and proliferation and migration speed were measured. In 20 dogs, the autologous jugular veins were interposed into the carotid arteries. For the study group (n=10), the graft was stored for 30 minutes in EGCG solution and 300mM EGCG was applied to the perivascular space after grafting. After 6 weeks, the intimal and medial thickness was measured. Result: The proliferation of RASMC and HUVEC was suppressed with EGCG. The migration of RASMC was suppressed with EGCG, but that of HUVEC was not affected. In the in vivo study, the intimal thickness was thinner in EGCG group than in the control group (p<0.05), but the medial thickness did not show any difference. The intimal/medial thickness ratio was lower in the EGCG group (p<0.05). Conclusion: EGCG suppresses intimal hyperplasia after vascular grafting, and this may be mediated by prevention of migration and proliferation of vascular smooth muscle cells. The use of EGCG may offer new therapeutic modality to prevent intimal hyperplasia.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.165-174
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• 1999

We explore the question of whether adenosine 5'-triphosphate (ATP) acts as an excitatory neurotransmitter in guinea-pig gastric smooth muscle. In an organ bath system, isometric force of the circular smooth muscle of guinea-pig gastric antrum was measured in the presence of atropine and guanethidine. Under electrical field stimulation (EFS) at high frequencies (＞20 Hz), NO-mediated relaxation during EFS was followed by a strong contraction after the cessation of EFS (a 'rebound-contraction'). Exogenous ATP mimicked the rebound-contraction. A known $P_{2Y}-purinoceptor$ antagonist, reactive blue 2 (RB-2), blocked the rebound-contraction while selective desensitization of $P_{2Y}-purinoceptor$ with ${\alpha},{\beta}-MeATP$ did not affect it. ATP and 2-MeSATP induced smooth muscle contraction, which was effectively blocked by RB-2 and suramin, a nonselective $P_2-purinoceptor$ antagonist. Particularly, in the presence of RB-2, exogenous ATP and 2-MeSATP inhibited spontaneous phasic contractions, suggesting the existence of different populations of purinoceptors. Both the rebound-contraction and the agonist-induced contraction were not inhibited by indomethacin. The rank orders of agonists' potency were 2-MeSATP > ATP ${ge}$ UTP for contraction and ${\alpha},{\beta}-MeATP\;{\ge}\;{\beta},{\gamma}-MeATP$ for inhibition of the phasic contraction, that accord with the commonly accepted rank order of the classical $P_{2Y}-purinoceptor$ subtypes. Electrical activities of smooth muscles were only slightly influenced by ATP and 2-MeSATP, whereas ${\alpha},{\beta}-MeATP$ attenuated slow waves with membrane hyperpolarization. From the above results, it is suggested that ATP acts as an excitatory neurotransmitter, which mediates the rebound-contraction via $P_{2Y}-purinoceptor$ in guinea-pig gastric antrum.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.487-494
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• 1996

The neurogenic responses of tracheal smooth muscles to electrical field stimulation (EFS) is biphasic, consisting firstly of cholinergic contraction followed by a slow and sustained relaxation. It is well known that a sustained relaxation involves the inhibitory non-adrenergic non-cholinergic systems. This study was done to Investigate the relaxing agents and their action mechanisms by use of an organ bath with plati- ilum . The tracheal smooth muscle relaxation due to EFS was suppressed by L-NAME, the WO (Nitric Oxide) synthase inhibitor, and these effects were reversed by L-arginine, the precursor of NO. Also, L-WAME (HG-nitro-L-arginine methyl ester) increased the basal tension. Nitroprusside, the NO-donor, suppressed the tracheal basal tension greatly. Methylene blue, the inhibitor of guanylate cyclase, decreased EFS-induced relaxations and increa ed basal tension. Forskolin and isoprenaline, which are activators of adenylate cyclase, suppressed tracheal basal tension in the same way as nitroprusside. TEA (tetraethylammonium), the non-specific K'channel blocker, and apamin, the Ca"-activated K'channel blocker, increased tracheal basal tension and EFS-induced relaxations. Our results indicate that Pr3 Is released upon stimulation of the NANC (Won Adrenergic Won Cholinergic) nerves in guinea-pig tracheal smooth muscle and that the release of NO related with the K+ channel, as well as the release of other inhibitory agents< e. g.)VIP (Vasoactive Intestinal Polypeptide), PHI (Peptide Histidine Isoleusine) > mediated via CAMP (cyclic Adenosine Monophosphate) may be Involved In sustained relaxation.

• Therapeutic Science for Rehabilitation
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• v.6 no.1
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• pp.71-83
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• 2017

Objective : This study aim is to identify whether smooth pursuit eye movement(SPEM) using portable device can alleviate chronic hemispatial neglect. Methods : We applied smooth pursuit eye movement to one chronic hemispatial neglect patient. Experimental duration was total 4weeks - 1week baseline, 2weeks SPEM intervention, 1week 2nd. baseline. The intervention was 10 SPEM sessions (30min each, 1session daily, from Monday to Friday) over a period of 2weeks. The neglect test carried out 5 times a week. The SPEM was provided on the screen when patient sat in front of the screen(8.4 inch tablet pc, distance 40cm). The SPEM video that the 24 yellow squares moving coherently from the right to the left side. Patients were instructed to perform smooth pursuit eye movement without head and neck movement. Results : As a result of the SPEM for 2weeks, the degree of neglect tended to decrease compared to baseline A. The degree of the LBT tended to increase the at the baseline A'. In contrast, the SCT showed that tendency which the degree of the neglect maintained at the baseline A'. Conclusion : We identified that SPEM using portable device is effective intervention method for chronic hemispatial neglect.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.119-128
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• 1997

The relaxation of gastric fundus smooth muscles is the primary physiological event which induces the receptive relaxation of monogastric animals. L-arginine/Nitric oxide(L-arg/NO) system is known to mediate the inhibitory non-adrenergic non-cholinergic(NANC) neurotransmission in various tissues including gastrointestinal smooth muscles. The longitudinal smooth muscles of porcine gastric fundus showed fast relaxation during electrical field stimulation(EFS) and rebound contraction after EFS in NANC condition. So, the purpose of present study was elucidation of the neurotrasmitters related to the NANC relaxation and explanation of the relation between NANC relaxation and L-arg/NO system. The longitdinal smooth muscles of porcine gastric fundus were hung in the organ bath and under the presence of guanethidine($5{\times}10^{-5}M$), precontraction was induced by carbachol($1{\times}10^{-6}M$). The muscle responses to EFS and drugs were isomerically recorded. The rusults were summarized as follows. 1. The longtudinal muscles of porcine gastric fundus showed frequency-dependent relaxation and rebound contraction to electrical field stimulaton(1ms, 8V, 1~16Hz, 20sec, EFS). These responses were blocked by tetrodotoxin($1{\times}10^{-6}M$). 2. The relaxation and rebound contraction of the longitudinal muscles of porcine gastric fundus to EFS were inhibited by L-NAME($2{\times}10^{-5}M$). The inhibitory effect of L-NAME was antagonized by L-arginine($1{\times}10^{-3}M$), but not by D-arginine($1{\times}10^{-3}M$). 3. Exogenous NO($NaNO_2$, $1{\times}10^{-5}{\sim}1{\times}10^{-4}M$, pH=2.0) caused concentration-dependent relaxation as EFS did. 4. Methylene Blue($2{\times}10^{-5}M$), a soluble guanylate cyclase inhibitor, inhibited the relaxation and rebound contraction of the longitudinal muscles of porcine gastric fundus induced by EFS, but N-ethlmaleimide, a adenylate cyclase inhibitor, did not. 5. 8-Br-cGMP($1{\times}10^{-6}{\sim}3{\times}10^{-6}M$), permeable cGMP analogue, induced dose-dependent relaxation. but 8-Br-cAMP($1{\times}10^{-6}{\sim}3{\times}10^{-6}M$), permeable cAMP analogue, did not. Both did not evoked rebound contraction. 6. ${\alpha}$-chymotrypsin did not affect the relaxation of the longitudinal muscles of porcine gastric fundus. 7. Reactive blue 2($1{\times}10^{-4}M$, 40min) siginificantly inhibited the rebound contraction induced by EFS and inhibited contraction caused by exogenous ATP($1{\times}10^{-4}{\sim}1{\times}10^{-3}M$). These results suggests that NANC relaxation of the longitudinal muscles of porcine gastric fundus mainly mediated by NO and the rebound contraction is related to NO and other neurotransmitters.

• The Korean Journal of Physiology
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• v.22 no.1
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• pp.13-29
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• 1988

In order to elucidate the regulatory mechanism of intracellular calcium ion concentrations, contractions or contractures induced by $Na^{+}-removal$, calcium-application or ouabain-treatment as an index of $Na^+/Ca^{2+}$ exchange activity were studied in atrial muscle or vascular smooth muscle (aorta and renal artery) of the rabbit. The magnitude of low sodium contractures in atrial trabeculae increased with sigmoid shape when external sodium concentrations were reduced to sodium-free condition, whereas that of calcium contracture intensified in a parabolic pattern when external calcium concentrations were elevated to 8 mM. $Na^{+}-removal$ contractures were induced in a duration-dependent manner to $K^{+}-free$ exposure and same findings were observed with ouabain treatment. $Na^{+}-free$ contractures were not affected by verapamil treatment, but stimulated by $100{\mu}M\;Mn^{2+}$ and inhibited by high concentrations of $Mn^{2+}\;(2{\sim}8mM)$ in a dose-dependent manner. Ryanodine which is known to suppress the release of calcium from internal store abolished spontaneous twitch contractions induced by $K^{+}-free$ solution, but had no effect on the development $Na^{+}-free$ contractures. Na-free contractures were not always induced in vascular smooth muscle preparations. Contractures by $O\;mM\;Na^+$ were usually seen in aorta, but not often in renal artery.$50\;mM\;K^+$, noradrenaline (NA) and angiotensin II (AII) always evoked very large contraction in all preparations of vascular smooth muscle. Contractures developed by $O\;mM\;Na^+$ were not sensitive to verapamil treatment as in atrial trabeculae, but were abolished by $100{\mu}M\;Mn^{2+}$. In contrast to $Na^{+}-free$ contractures, $Mn^{2+}(100{\mu}M)$ had no effect on the contractures induced by NA or 50 mM$K^+$. Caffeine in the concentration of 10 mM evoked transient contracture in the distal renal artery. The rate of spontaneous relaxation in caffeine contracture was dependent upon the concentrations of external sodium, and had double component of relaxation when the rate of relaxation was plotted in the semilogarithmic scale of relative tension versus time. Especially late components of relaxation had more direct relation to $Na^+$ concentrations. It could be concluded that $Na^+/Ca^{2+}$ exchange mechanism in the heart has a large capacity, inhibited by $Mn^{2+}$ but not by verapamil and ryanodine, while $Na^+/Ca^{2+}$ exchange system in vascular smooth muscle has a very low capacity especially in small artery, inhibited by low concentration of $Mn^{2+}\;(100{\mu}M)$ but not affected by verapamil and ryanodine.

• Journal of Industrial Convergence
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• v.21 no.10
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• pp.57-63
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• 2023

This study aims to elucidate the effect of glycyrrhizic acid on smooth muscle contraction and to determine the detailed mechanism incorporated. We hypothesized that glycyrrhizic acid played a role in the agonist-sensitive management of smooth muscle contraction. Stripped smooth muscles of Sprague-Dawley rats were prepared in organ baths and isometric tensions were converted, stored and analyzed by using isometric transducers, a physiograph and one way ANOVA. Interestingly, glycyrrhizic acid attenuated the thick filament regulating agonist (fluoride or thromboxane mimetic)-sensitive contraction (p=0.113, 0.008, 0.004 (Student's t-test), p=0.113, 0.008, 0.004 (One way ANOVA) at 0.01, 0.03, 0.1 mM fluoride, and p=0.156, 0.004, 0.003 (Student's t-test), p=0.156, 0.004, 0.003 (One way ANOVA) at 0.01, 0.03, 0.1 mM thromboxane mimetic) and did not attenuate the thin filament regulating agonist (phorbol ester)-induced contraction (p=0.392, 0.086, 0.065 (Student's t-test), p=0.392, 0.086, 0.065 (One way ANOVA) at 0.01, 0.03, 0.1 mM phorbol ester). It is suggesting that endothelial EDRF (NO) synthesis and accessory pathways besides endothelial EDRF (NO) synthesis such as ROCK restriction might be incorporated in the glycyrrhizic acid-induced modulation of smooth muscle contraction inhibiting acto-myosin interaction.