• Title/Summary/Keyword: Electric Stimulation

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Mechanism of Inhibitory Effect of Imipramine on Isolated Rat Detrusor Muscle in Relation to Calcium Modulation (흰쥐 적출 방광 배뇨근의 수축성에 대한 Imipramine의 작용과 Calcium동원 기전과의 관계)

  • Lee, Jong-Bum;Yoo, Kae-Joon;Ha, Jeoung-Hee;Kwon, Oh-Cheol;Lee, Kwang-Youn;Kim, Won-Joon
    • The Korean Journal of Pharmacology
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    • v.28 no.1
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    • pp.81-89
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    • 1992
  • Enuresis is a common voiding disorder among children. There are several therapeutic regimens for the disorder available today; behavioral therapies, psychotherapy, bladder training, sleep interruption, hypnosis and drug therapy. Recently, the efficacy of drug therapy has been acknowledged, particularly of antidepressants. Among the tricyclic antidepressants, imipramine is most frequently employed for the treatment of enuresis. Present study was undertaken to investigate the mechanism of imipramine on the contractility of urinary bladder in relation to the calcium modulation using isolated strips of rat detrusor urinae. 1. The electric fileld stimulation-induced contraction was abolished by imipramine, but partially inhibited by atropine. 2. Imipramine reduced the basal tone and diminished the phasic activity of detrusor muscle concentration-dependently, which was similar to that of diltiazem, a calcium channel blocker. 3. Imipramine suppressed the maximal responses and shifted the concentration-response curves of bethanechol and ATP to right. 4. Imipramine inhibited the calcium-induced recovery of tension in calcium-free physiologic salt solution (PSS) with a mode of action similar to that of diltizaem. 5. A23187, a calcium ionophore recovered the basal tone which had been reduced by imipramine in normal PSS. 6. In calcium-free PSS, A23187 could recover the abolished basal tone with the pretreatment of imipramine, but it exerted a partial recovery with the pretreatment of TMB-8, an inhibitor of intracellular calcium release. Based on these results, it is suggested that the inhibitory action of imipramine on the detrusor muscle exerted in part by blockade of the muscarinic and purinergic receptors, and interference with the influx of extracellular calcium, but not with the release of intracellular stored calcium, is involved in its mechanism of action.

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Factors Affecting Electrofusion of Plant Protoplasts (식물 Protoplast의 전기자극 융합에 관여하는 인자)

  • Han, Sung-Kyu;U, Zang-Kual;Kang, Soon-Suon;Riu, Key-Zung;Oh, Sung-Gug
    • Applied Biological Chemistry
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    • v.33 no.1
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    • pp.93-100
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    • 1990
  • The optimum conditions of electric stimulation for electrofusion of protoplasts of petunia, carrot and soybean, and the effects of calcium, magnesium, protease, trypsin, triton X-100, concanavalin A, dimethyl sulfoxide(DMSO), glycerol monooleate and spermine on fusion frequency and/or viability of petunia protoplast were investigated. The optimum frequencies(Hz)-amplitudes(V/cm) of AC Pulse for protoplast pearl-chain formation were 10 kHz-20 V/cm and 1 MHz-60 V/cm for petunia, 100 kHz-40 V/cm and $1\;MHz-40{\sim}60\;V/cm$ for carrot, and $1\;MHz-40{\sim}80\;V/cm$ for soybean, respectively. The optimum condition of DC pulse treatment at the 1 MHz-60 V/cm-15sec treatment of AC for electrofusion of petunia protoplasts was 2.5 kV/cm-40 sec, and under this condition the fusion frequency and viability of protoplasts were 45 % and 10 %, respectively, Both of the protoplasts of carrot and soybean were not fused under the AC and DC conditions tested in this experiment. The electrofusion of petunia protoplasts was stimulated by calcium, and the fusion frequency and the viability of the protoplasts were 43 % and 11 % , respectively at the calcium concentration of 140 mM. Although fusion frequency was not affected by magnesium only, magnesium stimulated fusion frequency in the presence of calcium, and the viability and fusion frequency of petunia protoplasts were 45 % and 13 %, respectively, at 140 mM of magnesium-140 mM of calcium. The relative fusion frequencies of petunia protoplasts to the controls were increased by 2.4, 2.1, 1.6, 1.4, 1.8, 1.5 and 2.2 folds, respectively, by the treatments of protease, trypsin, triton X-100, concanavalin A, DMSO, glycerol monooleate, and spermine. The viabilities of petunia protoplasts were decreased by these substances.

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Studies on the Utilization of Woodland for Livestock Farming II. Problem and Its Improvement Followed by the Join Cattle Grazing in king Won Do (임지의 축산적 이용에 관한 연구 제2보. 강원도의 새마을 "소" 임간공동방목사업의 문제점과 개선책)

  • 맹원재;윤익석;유제창;정승헌
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.3 no.2
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    • pp.100-111
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    • 1983
  • The research results reported herein had the objectives to understand and analyze the present problems of saemaeul woodland joint cattle grazing system in Kang Won Do and to take steps of improvement. The study results on actual management conditions, problems analyzed and improvement plan of total 208 joint cattle grazing area which was established 105 area in 1981 and 103 area in 1982 were summarized as follows: 1. the effectiveness of joint cattle grazing projects 1) Average daily weight gain of cattle during joint cattle grazing period was 0.4kg, showing higher daily than the conventional feeding of 0.33kg. 2) Increase of total farm income over the conventional feeding system were \1,031,357,320 during the grazing period from May to October in 1982 by adapting the 208 joint cattle grazing system, of which effectiveness of weight gain was \293,075,300 and labor saving was \543,838,750. 3) According to the results of questionaire investigation from 208 joint cattle grazing area, effectiveness of joint cattle grazing system over the conventional system were (1) labor saving, (2) feed cost saving, (3) reduced diseases, (4) increase of number of feeding, (5) inspiration of joint endeavor, (6) effect of more gain, (7) easiness of feeding and feed cost savings. 2. Problems of joint cattle grazing system. 1) Shortages of grass were a problem at second year of joint cattle grazing period due to the low regrowth rate of wild grass. 2) Proper land for woodland joint cattle grazing is belonging to land of Government ownership and it is very hard to get the permission from office of forestry for cattle grazing purpose. 3) It is also difficult to find a proper time of breeding in grazing area by the difficulty of estrus detection. 4) There are a difficulty to give a proper vaccination and medical examination for the grazing cattle. 3. Improvement plans for woodland joint cattle grazing projects. 1) Obtain sufficient roughages by hoof cultivation and oversowing pasture from the second year of joint cattle grazing period. 2) In order to increase the beef production and to use for a calf production area, Government should arrange that all proper grazing land of Government owned in Kang Won Do convert into woodland joint cattle grazing area. 3) Make a good reproductive record by mixed grazing with a excellent breeding cow in a remote area. And carry out the collective artificial insemination with synchronous puberty induced by injection of puberty stimulation hormone. 4) Make a preventive injection for blackleg, twice medication of fasciola hepatica in a year, and spray and medication of tick insecticide. 4. A policy towards upbringing of woodland joint cattle grazing area. 1) Government should thoroughly investigate about a proper land for woodland joint cattle grazing from all forests. 2) When the area is suitable for the woodland joint cattle grazing, though it is national forest or restricted area, government should make it possible to establish a grazing area. 3) On the proper land foe joint cattle grazing in the remote place, Government should support for the road construction and electric fence equipments by using of national funds. 4) There should be an administrative consideration for well promotion of the project that make woodland joint cattle grazing suitable to the characteristics of Kang Won Do. 5) In order to improve the reproduction record, Government should reform the insufficiency of artificial insemination in the joint cattle grazing area. 6) In order to maintain a proper price of cow, Government should carry out the price plan. 7) When there is any request for grassland formation in the woodland joint cattle grazing area, Government should permit it with preference.

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