• Title/Summary/Keyword: Muscle Property

Search Result 95, Processing Time 0.025 seconds

Encainide, a class Ic anti-arrhythmic agent, blocks voltage-dependent potassium channels in coronary artery smooth muscle cells

  • Hongliang Li;Yue Zhou;Yongqi Yang;Yiwen Zha;Bingqian Ye;Seo-Yeong Mun;Wenwen Zhuang;Jingyan Liang;Won Sun Park
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.27 no.4
    • /
    • pp.399-406
    • /
    • 2023
  • Voltage-dependent K+ (Kv) channels are widely expressed on vascular smooth muscle cells and regulate vascular tone. Here, we explored the inhibitory effect of encainide, a class Ic anti-arrhythmic agent, on Kv channels of vascular smooth muscle from rabbit coronary arteries. Encainide inhibited Kv channels in a concentration-dependent manner with an IC50 value of 8.91 ± 1.75 μM and Hill coefficient of 0.72 ± 0.06. The application of encainide shifted the activation curve toward a more positive potential without modifying the inactivation curve, suggesting that encainide inhibited Kv channels by altering the gating property of channel activation. The inhibition by encainide was not significantly affected by train pulses (1 and 2 Hz), indicating that the inhibition is not use (state)-dependent. The inhibitory effect of encainide was reduced by pretreatment with the Kv1.5 subtype inhibitor. However, pretreatment with the Kv2.1 subtype inhibitor did not alter the inhibitory effects of encainide on Kv currents. Based on these results, encainide inhibits vascular Kv channels in a concentration-dependent and use (state)-independent manner by altering the voltage sensor of the channels. Furthermore, Kv1.5 is the main Kv subtype involved in the effect of encainide.

On Estimation of Indication, Property and Processing of Rhus Verniciflua Stokes (옻의 주치(主治).효능(效能).수치법(修治法)에 관(關) 소고(小考);11종 한약서를 중심으로)

  • Eom, Seok-Ki;Kim, Kyung-Suk
    • Journal of Korean Medical classics
    • /
    • v.21 no.2
    • /
    • pp.29-37
    • /
    • 2008
  • Based on 11 Classics of Materia Medica designated by Ministry of health and welfare bulletin 1995-15 as legal basis in scope and preparation of herbal prescription, we reviewed indication, property and processing of Rhus Verniciflua Stokes which appear extensively in literature since earlier Joseon Dynasty. Following is the conclusion of this review after comparing with 'Korean Pharmacopoeia: commentary on herbal product standard'. 1. The properties of Rhus Verniciflua Stokes in 'Korean Pharmacopoeia :commentary on herbal product standard' should be changed as 'Tonifying the middle, restoring the muscle, fulfilling marrow, breaking old static blood, tonifying and activating after removing mass, unblocking the meridian, killing worms' and indication should be changed as 'Old static blood, deep rooted mass, wind-cold-dampness arthralgia, cough, 9 types of chest pain, abdominal or flank accumulation of stagnated qi[氣], amenorrhea, hernia mass, small bowel or bladder colic pain, abdominal pain due to worm accumulation'. 2. The processing of Rhus Verniciflua Stokes in 'Korean Pharmacopoeia: commentary on herbal product standard' should include 'natural drying or steaming drying followed by grinding and stir-baking until ripened or smoking appears'.

  • PDF

Design and embodiment of variableness band style magnetic field nerve stimulation system that apply $1^{trigger}$ $2^{mode}$ magnetic field treatment Probe for disease treatment

  • Kim, Whi-Young;Park, Sung-Joon
    • Journal of information and communication convergence engineering
    • /
    • v.6 no.4
    • /
    • pp.411-416
    • /
    • 2008
  • When compose magnetic field curer by belt and band style and need by magnetic field ripple last month, produce self-discipline roof. Bred in muscle disease (lumbago, backbone disease, corpulence) back. Result that study, manufactured various variableness band style - magnetic field probe firstly. Can establish self-discipline treatment pulse price by disease secondly. Could seek correct variableness band punishment, - magnetic field probe relationship implementation and property in waist, and so on, shoulder, neck, arm, leg, ankle, wrist etc. by third. Could find variableness band style energy value that need in-magnetic field Probe's treatment by fourth. This research could design pulse of self-discipline in band form and apply each according to disease.

Nano Carbon Material Based Electrochemical Actuators (탄소 나노 재료 기반의 전기-화학적 구동기)

  • Cha, Ju-Young;Kang, In-Pil
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.28 no.11
    • /
    • pp.1251-1258
    • /
    • 2011
  • With the help of nanoscale materials like carbon nanotube (CNT), there is the potential to develop new actuators that will provide higher work per cycle than previous actuator technologies, and generate much higher mechanical strength. In this study, the electrochemical actuation characteristics of nano carbon materials were experimentally studied to develop electrochemical actuators. The electrochemical actuators were composed of aqueous NaCl electrolyte and their actuating electrodes were made of multi-walled carbon nanotube (MWCNT)/polystyrene composite and graphene respectably. Actuation is proportional to charging transfer rate, and the electrolysis with an AC voltage input has very complex characteristics. To quantify the actuation property, the strain responses and output model were studied based on electrochemical effects between the nano carbon films and the electrolyte.

Study on a test method for the endurance of myoelectric hand prosthesis (근전의수의 내구성 시험방법에 대한 연구)

  • Choi, K.W.;Mun, M.S.
    • Journal of rehabilitation welfare engineering & assistive technology
    • /
    • v.5 no.1
    • /
    • pp.11-15
    • /
    • 2011
  • This paper propose the test method for a performance of the myoelectric hand prosthesis(MHP) controlled according to the myoelectric signal generated in the human muscle. The MHP consists of a mechanical hand, a surface myoelectric sensor(SMES) for a measuring myoelectric signal, a control system and a charging battery. The two commercialized MHP is tested for the grip endurance property. The test results is not difference a noise and a grip force. The proposed test method is proved the reliability of MHP by the endurance test.

Effect of Variation of Membrane Thickness on the Activity of $Ca^{2+}$-activated $K^+$ Channel in Planar Lipid Bilayers

  • Seo, Hyoung-Sik;Ryu, Pan-Dong
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1999.06a
    • /
    • pp.56-56
    • /
    • 1999
  • Change of membrane property can affect the activity of membrane proteins. In this work, we investigated the single channel properties of large conductance $Ca^{2+}$-activated $K^{+}$(BK) channels in planar lipid bilayers of different thickness. First, we recorded the activity of single BK channels from rat skeletal muscle incorporated into the control bilayer, then increased the bilayer thickness by perfusing the recording solution with the one saturated with n-pentane, or reduced the thickness by adding diheptanoylphosphatidylcholine (di$C_{7:0}$PC) to the recording soluton.(omitted)

  • PDF

A Study on Optical Properties in Biological Tissue Using A Photon Path Diffusion Model (광 항적경로 모델을 이용한 피하조직에서의 광 특성에 관한 연구)

  • 임현수
    • Journal of Biomedical Engineering Research
    • /
    • v.15 no.3
    • /
    • pp.265-274
    • /
    • 1994
  • This paper proposes a method of noninvasive reflectance light to measure the blood fractional volume (Vb) and oxygen saturation ($SO_2$) of biological tissue. We chose the red light of 660nm and infrared light of 880nm. In Vivo reflectance data were obtained by the physiological changes front the surface of the skin over the calf in human subject. The reflected light intensity from different layers within a biological tissue was measured by specially designed reflectometer to apply photon path diffusion model. The collected data represent the changes of blood (ractional volume and oxygen saturation at each reflected light wavelengths. The data evaluation was assessed by examining the slopes of the plotted indices for the changes in oxygen saturation and blood (ractional volume. The results presented in this paper claim that light reflectance can separately discriminate the change of blood volume and that of oxygenation in muscle and also in skin.

  • PDF

Neuropharmacological Activity of Humulus lupulus Extracts

  • Lee, Kang-Mee;Jung, Jun-Sub;Song, Dong-Keun;Kim, Yung-Hi
    • Korean Journal of Pharmacognosy
    • /
    • v.24 no.3
    • /
    • pp.231-234
    • /
    • 1993
  • Neuropharmacological profile of Humulus lupulus (hop) extract was studied in mice. At doses above 100 mg/kg(i.p.), it decreased spontaneous locomotor activity and raised the nociceptive threshold in the hot-plate test. At doses above 250 mg/kg (i.p.), it increased pentobarbital-induced sleeping time and produced muscle relaxant effect. At the dose of 500 mg/kg, anticonvulsive effect against pentylenetetrazole-induced convulsion and hypothermic effect was observed.

  • PDF

Physico-chemical Meat Qualities of Loin and Top Round Beef from Holstein Calves with Different Slaughtering Ages

  • Cho, Soohyun;Kang, Sun Moon;Seong, Pilnam;Kang, Geunho;Choi, Sunho;Kwon, Engki;Moon, Sungsil;Kim, Donghun;Park, Beomyoung
    • Food Science of Animal Resources
    • /
    • v.34 no.5
    • /
    • pp.674-682
    • /
    • 2014
  • The objective of this study was to investigate the physico-chemical and sensory properties of loin (m. longissimus dorsi) and top round (m. semimembranosus) beef from 3-, 6-, 9-, and 12 mon-old Holstein calves. For both loin and top round muscles, the moisture contents were decreased, whereas the protein and fat contents were increased, as the slaughtering age increased. In terms of meat color, for both muscle types, CIE $L^*$ values were decreased, whereas CIE $a^*$ values and myoglobin content increased as the slaughtering age increased. pH values were significantly higher in the 3 mon-old group than in the other groups. The Warner-Bratzler shear force (WBSF) values were lowest for loin muscles from the 12 mon-old group; however, there was no significant difference for top round muscle among the 4 age groups. Cooking loss for both loin and top round muscles were significantly higher for the 3 mon-old group than for the other groups. The water holding capacity (WHC) of both muscles were highest for the 12 mon-old groups (p<0.05). In fatty acid composition of the 12 mon-old groups, loin muscles had significantly higher levels of C14:0, C16:1n7, C18:1n9, and mono-unsaturated fatty acids (MUFA), and top round muscles had significantly higher levels of C16:1n7, C18:1n7, C18:1n9, MUFA, MUFA/SFA. Loin muscle from the 3- and 12 mon-old groups had significantly higher scores for tenderness and overall likeness. Top round muscle from the 9- and 12 mon-old groups had significantly higher scores for overall likeness than those from the other age groups.

Effect of Deboning Time on Quality Characteristics of Pressed Pork Ham (돈육 뒷다리 부위의 발골시간이 프레스햄의 품질 특성에 미치는 영향)

  • Yang, H.S.;Joo, S.T.;Park, Gu-Boo
    • Journal of Animal Science and Technology
    • /
    • v.49 no.3
    • /
    • pp.387-394
    • /
    • 2007
  • To investigate the effects of deboning time and muscle type of ham on quality characteristics of cooked press ham, a total of twelve pigs(barrow, 100±5kg) were slaughtered and split in half. The left side ham of carcasses was deboned immediately after slaughter whereas the right side ham was deboned after chilling for 24 hours at 4℃. Each of two muscles(SM; Semimembranosus, BF; Biceps femoris) was used to make a press ham. The pH of hot-boning muscles was significantly(p<0.05) higher than that of cold- boning muscles, and the pH of SM samples was significantly(p<0.05) higher than BF samples. Hot-boning muscles showed significantly(p<0.05) longer sarcomere length compared with cold-boning muscles. There was no significant difference in myoglobin(Mb) percentage between SM and BF muscles, but SM samples of hot-boning showed significantly(p<0.05) lower L* value compared to hot-boning BF samples. The lightness(L*) of hot-boning muscles was significantly(p<0.05) lower than that of cold-boning muscles. These results suggested that the dark color of hot-boning samples might be due to not only the high muscle pH but also the long sarcomere length without difference in Mb percentage. Hardness and gumminess of hot-boning press ham were significantly(p<0.05) lower than those of cold-boning samples. These results implied that color and pH of press ham did not affected by deboning time or muscle type of ham. However data suggested that texture and panel test of press ham might be improved by using hot-boned muscle due to long sarcomere length of raw meat.