• The Journal of Internal Korean Medicine
• /
• v.11 no.1
• /
• pp.165-177
• /
• 1990

In order to study the effects of HWA GAE SAN known clinically for their effects of treatment for cough and asthma, the study was carried out to investigate the effect of HWA GAE SAN extract on the contractile force of isolated guinea pig trachea smooth muscle and elucidate its mechanism. The results were obtained as follows. 1. Preparation of isolated guinea pig trachea smooth muscle was suspended in the oxygeneted Kreb's Henseleit bicarbonate buffer solution at $37^{\circ}C$ and recorded the developed tension by the drug with the isometric transducer (Nacro F-60). The restin tension was approximately 0.5g. 2. The trachea smooth muscle in normal state showed a significant atony to the increase of density of HWA GAE SAN. 3. The atonic effect of the trachea smooth muscle was restricted after prescription of Pyrilamine& Cyproheptadine. Hireceptor broker, which were prearranged. 4. After 5, 15, 50& $150{\mu}l/ml$ of HWA GAE SAN were prescribed, the atony of trachea smooth muscle was caused by Histamine. 5. After 50& $150{\mu}l/ml$ of HWA GAE SAN were prescribed, the atony of trachea smooth muscle was remarkably dwindled which was caused by Acetylcholine. 6. After $150{\mu}l/ml$ of HWA GAE SAN were prescribed, the atony of trachea smooth muscle was remarkably dwindled which was caused by 5-Hydroxytryptamine.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.7
• /
• pp.1339-1342
• /
• 2007

In this study, we determined the optimum electrode pair for measuring the abdominal pressure using bio-impedance method and compared with conventional methods. Because impedance changes differ from a weight, a height, contractile force, volume of muscle and blood other or whatever of individuals, it was quantified using values of impedance change, correlation coefficient and SNR. Our results showed the optimum electrode pair (1, 9) which could detect impedance changes due to an increase of the intensity of the abdominal pressure. The correlation coefficient and quadratic function between the RMS values of EMG and the impedance changes were 0.87 and $y=0.0014x^2+0.0620x+0.6958$, respectively. It demonstrated that the abdominal pressure could be measured noninvasively and simply using bio-impedance method. We propose that this optimum electrode configuration would be useful for future studies involving the convenient measurement of abdominal pressure by ambulatory urodynamics monitoring study.

• The Korean Journal of Pharmacology
• /
• v.10 no.1 s.15
• /
• pp.47-52
• /
• 1974

The isolated rabbit gall bladder strips were prepared according to the technique described by Amer and Becvar (1969). The strips were placed in a bath containing 100 ml of Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The tension of the muscle strip was initially adjusted to 0.7g. The contractile response was measured isometrically by a force-displacement transducer connected to a polygraph. The effect of a number of autonomic drugs were studied for their interaction with caerulein (Prof. V. Erspamer, F.I. 6934 Caerulein, Farmitalia, Italia), a gastrin or CCK.PZ like peptide, on isolated rabbit gall bladder strips. In this preparation caerulein produced contractions of CCK-PZ type, but the relative potency on a weight basis was 40 times that of CCK-PZ. The response of caerulein was not modified by either cholinergic or alpha or beta adrenergic blockade. However, the response of caerulein and of barium on the strips were prevented by papaverine or aminophylline. Isoproterenol, papaverine or aminophylline alone relaxed the preparation whereas caerulein, CCK-PZ, acetylcholine, serotonin, histamine or barium chloride contracted the preparation. In summary, it is concluded that caerulein on the gall bladder strip seems to act independently of the autonomic nervous system and mediated via mechanisms apparently similar to those involved in the action of barium chloride.

• The korean journal of orthodontics
• /
• v.42 no.2
• /
• pp.64-72
• /
• 2012

Objective: The aims of this study were to examine whether a passive stretch stimulus by means of a functional appliance induces changes in the fiber composition of masticatory muscles and whether these changes are similar to the changes in stretched limb muscle fibers by using RT-PCR, western blot, and immunohistochemical assays. Methods: Five male New Zealand White rabbits were fitted with a prefabricated inclined plane on the maxillary central incisors to force the mandible forward (- 2 mm) and downward (- 4 mm). Further, 1 hind limb was extended and constrained with a cast so that the extensor digitorum longus (EDL) was stretched when the animal used the limb. The animals were sacrificed aft er 1 week and the masseter, lateral pterygoid, and EDL were processed and compared with those from control animals (n = 3). Results: The stretched EDL had a significantly higher percentage of slow fibers, whereas the stretched masticatory muscles did not show changes in the composition of the major contractile proteins aft er 7 days. Conclusions: The transition of fiber phenotypes in response to a stretch stimulus may take longer in the masticatory muscles than in the limb muscles.

• Molecules and Cells
• /
• v.39 no.10
• /
• pp.722-727
• /
• 2016

Cardiomyopathy is a major cause of death worldwide. Based on pathohistological abnormalities and clinical manifestation, cardiomyopathies are categorized into several groups: hypertrophic, dilated, restricted, arrhythmogenic right ventricular, and unclassified. Dilated cardiomyopathy, which is characterized by dilation of the left ventricle and systolic dysfunction, is the most severe and prevalent form of cardiomyopathy and usually requires heart transplantation. Its etiology remains unclear. Recent genetic studies of single gene mutations have provided significant insights into the complex processes of cardiac dysfunction. To date, over 40 genes have been demonstrated to contribute to dilated cardiomyopathy. With advances in genetic screening techniques, novel genes associated with this disease are continuously being identified. The respective gene products can be classified into several functional groups such as sarcomere proteins, structural proteins, ion channels, and nuclear envelope proteins. Nuclear envelope proteins are emerging as potential molecular targets in dilated cardiomyopathy. Because they are not directly associated with contractile force generation and transmission, the molecular pathways through which these proteins cause cardiac muscle disorder remain unclear. However, nuclear envelope proteins are involved in many essential cellular processes. Therefore, integrating apparently distinct cellular processes is of great interest in elucidating the etiology of dilated cardiomyopathy. In this mini review, we summarize the genetic factors associated with dilated cardiomyopathy and discuss their cellular functions.

• Journal of Biomedical Engineering Research
• /
• v.17 no.1
• /
• pp.43-48
• /
• 1996

We investigated the energistics of the physiological heart model by comparing predictive indexes of the myocardial oxygen consumption (MOC), such as tension-time index (R), tension-time or force-time inteual (FTI), rate-pressure product (RPP), pressure-work index, and systolic pressure-volume area (PVA) when using the electro-hydraulic left ventricular device (LVAD). We developed the model of LVAD incorporated the closed-loop cardiovascular system with a baroreceptor which can control heart rate and time-varying elastance of left and right ventricles. On considering the benefit of the LVAD, the effects of various operation modes, especially timing of assistance, were evaluated using this coupled computer model. Overall results of the computer simulation shows that our LVAD can unload the ischemic (less contractile) heart by decreasing the MU and increasing coronary flow. Because the pump ejection at the end diastolic phase of the natural heart may increase the afterload of the left ventricle, the control scheme of our LVAD must prohibit ejecting at this time. Since the increment of coronary flow is proportional to the peak aortic pressure after ventricle contraction, the LVAD must eject immediately following the closure of the aortic valve to increase oxygen availability.

• The Korean Journal of Pharmacology
• /
• v.11 no.1 s.17
• /
• pp.15-18
• /
• 1975

The effect of skin extracts of Korean amphibian, poisonous snake and fresh-water fish were determined for their caerulein-like action on rabbit gall bladder strips. The isolated gall bladder strips were prepared according to the technique described by Amer and Becvar(1969). The strips were placed in a bath containing 100ml of Locke-Ringer solution maintained at $38^{\circ}C$. Oxygen was continuously bubbled through the solution. The tension of the muscle strip was initially adjusted to 0.7g. The contractile response was measured isometrically by a force-displacement transducer connected to a polygraph. In this rabbit gall bladder strip caerulein produced contraction of CCK-PZ type. The skin extract of Korean amphibian also elicited similar contraction as caerulein, which extracted from Australian amphibian, Hyla caerulea, by Erspamer et al. The calculated amount was approximately $2{\mu}g$ caerulein per gram of skin tissue in Korean amphibian and the potency was about 1/200 of that seen in Australian amphibian. The contraction of gall bladder strip by our amphibians occurs in decreasing order; Rana Nigromaculata coreana Okada, Rana nigromaculata Hallowell, Hyla arborea japonica Gunther and Bombina orientalis Boulenger. The skin extracts of poisonous snake and fresh-water fish produced no caerulein-like activity.

• YAKHAK HOEJI
• /
• v.32 no.2
• /
• pp.129-136
• /
• 1988

Effects of the selective alpha-adrenoceptor agonists, clonidine, oxymetazoline and phenylephrine, on heart rate and contractile force were investigated in the isolated frog atria and it was attempted to examine the influence of adrenoceptor antagonist upon those. Clonidine produced dose-dependent negative chronotropic and positive inotropic effects. The negative chronotropic effect was significantly attenuated in the presence of prazosin and yohimbine but not propranolol. The positive inotropic effect was significantly attenuated by prazosin, yohimbine and propranolol. Oxymetazoline produced dose-dependent negative chronotropic and inotropic effects. The negative chronotropic effect was significantly attenuated in the presence of prazosin, which was partially augmented by yohimbine but was not affected by propranolol. The negative inotropic effect was not affected by propranolol but it was partially augmented by yohimbine and was partially attenuated by prazosin. Phenylephrine produced dose-dependent positive chronotropic and inotropic effects. The positive chronotropic and inotropic effect were significantly attenuated in the presence of propranolol but were not affected by prazosin and yohimbine. These results suggest that the negative chronotropic effect by clonidine and oxymetazoline is mediated by alpha-adrenoceptors, the positive chronotropic and inotropic effects by phenylephrine are mediated by beta-adrenoceptors, and alpha-adrenoceptors mediated the inhibitory chronotropic responses exists in the isolated frog atria.

• Korean Journal of Pharmacognosy
• /
• v.15 no.1
• /
• pp.24-29
• /
• 1984

It was previously reported from our laboratory that the rate of deterioration of contractile force was slower in the heart of the ginseng extract treated rats. It was also found that ginseng may have an ability to sustain the normal function of the heart by sustaining Ca accumulation by sarcoplasmic reticulum. $Ca^{++}-dependent$ ATPase plays the central role in movement of $Ca^{++}$ ion from sarcoplasm into sarcoplasmic reticulum. In this investigation, the fragment of sarcoplasmic reticulum was prepared from rat heart treated with ginseng water extract orally 100mg/kg/day for 7 to 10 days and from normal rat heart. $Ca^{++}-dependent$ APTase activity was estimated by a modified method of Fiske and Subbarow's procedure. Experimental groups were divided into 6 groups, depending on the preincubation time, 5, 30 and 60min. at ${25}^{\circ}C$ and ${37}^{\circ}C$ respectively. In both of the groups of ${25}^{\circ}C$ and ${37}^{\circ}C$, $Ca^{++}-dependent$ ATPase activities of the ginseng treated rat hearts were higher than that of normal hearts. Therefore, it can be concluded that $Ca^{++}-dependent$ ATPase activities in sarcoplasmic reticulum of rat hearts were increased by the treatment with ginseng extract.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.16 no.2
• /
• pp.322-326
• /
• 2002

Artemisia iwayomogi has been used in Korea for many centuries as a treatment for anemia. The effect of Artemisia iwayomogi on tracheal smooth muscle is not known. The purpose of the present study is to determine the effect of Artemisia iwayomogi on histamine induced tracheal smooth muscle contraction in guinea pigs. Guinea pigs(500g, male) were killed by CO₂ exposure and a segment (8-10mm) of the thoracic trachea from each rat and guinea pig was cut into equal segments and mounted ‘in pairs’ in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine (His) which evoked 50% of maximal response (ED/sub 50/) was obtained from cumulative dose response curves for histamine (10/sup -7/～10/sup -4/M). Contractions evoked by His (ED/sub 50/) were inhibited significantly by Artemisia iwayomogi. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 31.9% (p<0.05) after 100㎕/㎖ Artemisia iwayomogi. L-NNA slightly but significantly attenuated the inhibitory effects of Artemisia iwayomogi. Following treatment with L-NNA, the mean percent inhibition caused by 100㎕/㎖ Artemisia iwayomogi fell to 44.6% in guinea pig induced by histamine contraction. Propranolol, indomethacin and methylene blue did not significantly alter the inhibitory effect of Artemisia iwayomogi. These results indicate that Artemisia iwayomogi can relax histamine induced contraction of guinea pig, and that this inhibition related to nitric oxide formation.