• Title/Summary/Keyword: induced potential

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Drought Stress Influences Photosynthesis and Water Relations Parameters of Synurus deltoides (건조스트레스가 수리취의 광합성 및 수분관련 특성에 미치는 영향)

  • Lee, Kyeong-Cheol;Lee, Hak Bong
    • Journal of Korean Society of Forest Science
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    • v.106 no.3
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    • pp.288-299
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    • 2017
  • This study was conducted to find out the influence of drought stress on physiological responses of Synurus deltoides. Drought stress was induced by withholding water for 25 days. Leaf water potentials were decreased of both predawn (${\Psi}_{pd}$) and mid-day (${\Psi}_{mid}$) with increasing drought stress, but water saturation dificit (WSD) was 7 times increased. ${\Psi}_{pd}-{\Psi}_{mid}$ showed the significant difference of 0.22~0.18 MPa in stressed before 10 days, and nonsignificant as treatment time became longer. A strong reduction of stomatal conductance ($gH_2O$) and stomatal transpiration rate (E) were observed after 15 days of drought stress Significant reductions of net apparent quantum yield (${\Phi}$) and maximum photosynthesis rate ($Pn_{max}$) were observed after 20 days of drought stress; However, water use efficiency (WUE) was shown the opposite trend. This implies that decrease of photosynthesis rate may be due to an inability to regulate water and $CO_2$ exchanged through the stomata. From JIP analysis, flux ratios (${\Psi}_O$ and ${\Phi}_{EO}$) and performance index on absorption basis ($PI_{ABS}$) were dramatically decreased withholding water after 15 days, which reflects the relative reduction of photosystem II activity. The leaf of S. deltoides showed osmotic adjustment of -0.35 MPa at full turgor and -0.40 MPa at zero turgor, and also cell-wall elastic adjustment of 9.4 MPa, indicating that S. deltoides tolerate drought stress through osmotic adjustment and cell-wall elastic adjustment. The degree of change in water relations parameters such as Vo/DW, Vt/DW decreased with increasing drought stress. This result showed that S. deltoides was exhibited a strong reduction of photosynthetic activity to approximately -0.93 MPa of predawn leaf water potential, and both of osmotic adjustment and cell-wall elastic adjustment in drought stress condition appears to be an important adaptation for restoration in this species.

Pro-apoptotic and Anti-adipogenic Effects of Proso Millet (Panicum miliaceum) Grains on 3T3-L1 Preadipocytes (기장(Panicum miliaceum)의 마우스 3T3-L1 세포에 대한 에폽토시스 유발 및 지방세포형성 억제 효능)

  • Jun, Do Youn;Lee, Ji Young;Han, Cho Rong;Kim, Kwan-Pil;Seo, Myung Chul;Nam, Min Hee;Kim, Young Ho
    • Journal of Life Science
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    • v.24 no.5
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    • pp.505-514
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    • 2014
  • To examine the anti-obese activity of miscellaneous cereal grains, 80% ethanol extracts from eight selected miscellaneous cereal grains were compared for their cytotoxic effects on 3T3-L1 murine preadipocytes. The ethanol extract of proso millet exhibited the highest cytotoxicity. Further fractionation of the ethanol extract with methylene chloride, ethyl acetate, and n-butanol showed that the cytotoxicity of the ethanol extract was mainly partitioned into the butanol fraction. As compared with differentiated mature adipocytes, 3T3-L1 preadipocytes were more susceptible to the cyctotoxicity of the butanol fraction. When each organic solvent fraction (25 ${\mu}g/ml$) was added during the differentiation period for 6 days, the cell viability was not affected significantly except for the butanol fraction, but the intracellular lipid accumulation declined to a level of 81.5%~50.3% of the control. The Oil Red O staining data also demonstrated that the ethanol extract as well as the butanol fraction could inhibit the differentiation of 3T3-L1 preadipocytes into mature adipocytes. The presence of the butanol extract during the induced adipocytic differentiation also resulted in a significant reduction in the expression levels of critical adipogenesis mediators $(C/EBP{\alpha}$, $PPAR{\gamma}$, aP2, and LPL) to a barely detectable or undetectable level and the cells retained the fibroblast-like morphology of 3T3-L1. In 3T3-L1 cells, the cytotoxicity of the butanol fraction (50-100 ${\mu}g/ml$) was accompanied by mitochondrial membrane potential (${\Delta}{\psi}m$) loss, caspase-3 activation, and PARP degradation. Taken together, these results indicate that proso millet grains possess pro-apoptotic and anti-adipocytic activities toward adipocytes, which can be applicable to prevention of obesity.

Ameliorating Effect of $\textrm{Ca}({NO_3})_2$ or $\textrm{CaCl}_2$ on the Growth and Yield of NaCl-Stressed Tomato Grown in Plastic Pots Filled with Soil (NaCl 스트레스를 받은 토마토의 생육 향상을 위한 $\textrm{Ca}({NO_3})_2$$\textrm{CaCl}_2$ 처리 효과)

  • 강경희;권기범;최영하;김회태;이한철
    • Journal of Bio-Environment Control
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    • v.11 no.3
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    • pp.127-132
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    • 2002
  • Enhanced supply of $Ca^{2+}$ as well as NO$_3$$^{[-10]}$ is known to restrict the uptake of the Na$^{+}$ and Cl$^{[-10]}$ ion and ameliorate growth under saline conditions. This test was conducted to investigate the ameliorating effects of Ca(NO$_3$)$_2$ or CaCl$_2$ on the growth and yield of NaCl-stressed tomato plants grown in plastic pot filled with soil. All treatments except for the control were supplied with 80 mM NaCl fur two weeks after transporting. The saline solutions with nutrient were supplemented with either 0, 10 or 20 mM Ca(NO$_3$)$_2$ and either 0, 10 or 20 mM CaCl$_2$ during harvesting time from two weeks after transporting. Ca(NO$_3$)$_2$ or CaCl$_2$ application enhanced the growth such as plant height, fresh weight, dry weight, fruit number, and fruit weight, and yield of NaCl-stressed tomato, and also their effects increased greater as concentration of supplemented Ca(NO$_3$)$_2$ or CaCl$_2$increased. Yield increased in 20 mM Ca(NO$_3$)$_2$ compared with the others except fur the control. Photosynthetic rate in Ca treatments was lower than that of the control, but higher than that of NaCl treatment. Leaf chlorophyll content was higher in Ca treatments compared with the others, especially in younger leaf, while that was not affected by concentration of supplemented Ca. Ca(NO$_3$)$_2$ or CaCl$_2$ supply increased the $K^{+}$ and $C^{2+}$ concentration of tomato plants, whereas the Na$^{+}$ transport to the leaves was inhibited. There was a strong increase in the $K^{+}$/Na$^{+}$ ratio in plants treated Ca(NO$_3$)$_2$, or CaCl$_2$. Cl$^{[-10]}$ content of plants was decreased by supplemental Ca(NO$_3$)$_2$ but Cl$^{[-10]}$ was increased in plants with CaCl$_2$compared with Ca(NO$_3$)$_2$. N concentration in plants of tomato increased with enhanced Ca(NO$_3$)$_2$ or CaCl$_2$supply, In conclusion, our study confirms the potential of Ca(NO$_3$)$_2$ or CaCl$_2$to alleviate NaCl-induced growth reductions in tomato.

Anti-Obesity Effects of Foeniculum fructus Water Extract (회향종자(Foeniculum fructus) 물 추출물의 항비만 효과)

  • Seo, Dong-Joo;Kim, Jeong-Mi;Kim, Tae-Hyuk;Baek, Jong-Mi;Kim, Tae-Woo;Kim, Hyun-Sook;Choe, Myeon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.11
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    • pp.1604-1610
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    • 2010
  • We investigated the anti-obesity effects of Foeniculum fructus water extract on body weight, epididymal adipocyte size, plasma lipid levels and activities of key enzymes such as lipoprotein lipase (LPL), acyl-CoA synthetase (ACS) in high fat diet-induced obese mice. Experimental groups were normal diet group (ND), high fat diet group (HFD), high fat diet with 0.05% orlistat group (HFDO), and high fat diet with 0.5% Foeniculum fructus group (HFDF). Eleven-weeks feeding with HFD resulted in significant increase in lipid levels, body weight, liver and epididymal adipose tissue weight, compared with the ND group. Diet containing Foeniculum fructus water extract significantly reduced plasma total cholesterol, triglyceride and glucose concentrations as well as body weight, liver and epididymal adipose tissue weights. Plasma LDL cholesterol levels were significantly lower in the HFDF group than those in HFDO group. LPL activities elevated by a high fat diet were significantly decreased by Foeniculum fructus water extract administration. ACS activities decreased in the high fat diet group and markedly increased in the Foeniculum fructus water extract administered group. All things considered, Foeniculum fructus water extract efficiently inhibits the inflow of fatty acid into the cell, and activates metabolic process that uses fatty acids flowing as an energy source. Thus, Foeniculum fructus water extract may have great potential as a novel anti-obesity agent.

A Study of the Characteristics of Heavy Rainfall in Seoul with the Classification of Atmospheric Vertical Structures (대기연직구조 분류에 따른 서울지역 강한 강수 특성 연구)

  • Nam, Hyoung-Gu;Guo, Jianping;Kim, Hyun-Uk;Jeong, Jonghyeok;Kim, Baek-Jo;Shim, Jae-Kwan;Kim, Byung-Gon
    • Journal of the Korean earth science society
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    • v.40 no.6
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    • pp.572-583
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    • 2019
  • In this study, the atmospheric vertical structure (AVS) associated with summertime (June, July, and August) heavy rainfall in Seoul was classified into three patterns (Loaded Gun: L, Inverted V: IV, and Thin Tube: TT) using rawinsonde soundings launched at Osan from 2009 to 2018. The characteristics of classified AVS and precipitation property were analyzed. Occurrence frequencies in each type were 34.7% (TT-type), 20.4% (IV-type), 20.4% (LG-type), and 24.5% (Other-type), respectively. The mean value of Convective Available Potential Energy (1131.1 J kg-1) for LG-types and Storm Relative Helicity (357.6 ㎡s-2) for TT-types was about 2 times higher than that of other types, which seems to be the difference in the mechanism of convection at the low level atmosphere. The composited synoptic fields in all cases showed a pattern that warm and humid southwesterly wind flows into the Korean Peninsula. In the cases of TT-type, the low pressure center (at 850 hPa) was followed by the trough in upper-level (at 500 hPa) as the typical pattern of a low pressure deepening. The TT-type was strongly influenced by the low level jet (at 850 hPa), showing a pattern of connecting the upper- and low-level jets. The result of analysis indicated that precipitation was intensified in the first half of all types. IV-type precipitation induced by thermal instability tended to last for a short term period with strong precipitation intensity, while TT-type by mechanical instability showed weak precipitation over a long term period.

The changes in signal-averaged electrocardiogram after surgical correction of congenital heart disease (선천성 심장병의 개심술 후 신호 평준화 심전도의 변화)

  • Kim, Yeo Hyang;Choe, Hee Jung;Kim, Gun Jik;Cho, Joon Yong;Hyun, Myung Chul;Lee, Sang Bum
    • Clinical and Experimental Pediatrics
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    • v.52 no.12
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    • pp.1364-1369
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    • 2009
  • Purpose : To analyze abnormal ventricular activation in childhood congenital heart disease induced by postoperative changes in ventricular volume and pressure and ventricular scar formation using signal-averaged electrocardiography (SAECG). Methods : Fifty-two patients who had undergone open heart surgery (OHS) were enrolled. Patients were divided into the following 3 groups: right ventricular volume overload (atrial septal defect, group1), left ventricular volume overload (ventricular septal defect, group2), and right ventricular pressure overload (tetralogy of Fallot, group 3). The patients were monitored by standard 12-lead ECG and SAECG before and 2 months after the operation. QRS duration, QT and QTc intervals, filtered QRS (f-QRS), high frequency low amplitude potential (HFLA), and root mean square (RMS) voltage in the terminal 40 ms of SAECG were determined. Results : In the preoperative period, group1 showed significant increase in QRS (P=0.011) compared to those of the other 2 groups. In the postoperative period, group3 showed significant increase in the QTc interval (P=0.004) compared to those in the other 2 groups. SAECG parameters showed no significant differences among the groups in the pre- or postoperative period. Of the 52 patients, 12 (23%) in the preoperative period and 21 (40%) in the postoperative period had at least 1 SAECG abnormality. The prevalence of SAECG abnormalities was significantly higher in the postoperative group 2 and group 3 (preoperative: 20% versus postoperative: 28%, P<0.001, preoperative: 14% versus postoperative: 64%, P<0.001, respectively). Conclusion : Abnormal SAECG patterns may be attributed to postoperative scars, OHS itself, and/or ventricular overload.

Effect of Silicate-Coated Rice Seed on Healthy Seedling Development and Bakanae Disease Reduction when Raising Rice in Seed Boxes (벼 상자육묘에서 규산코팅볍씨의 건묘육성과 벼키다리병 경감효과)

  • Kang, Yang-Soon;Kim, Wan Jung;Roh, Jae-Hwan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.62 no.1
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    • pp.1-8
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    • 2017
  • We investigated the effect of silicate coating of rice seeds on bakanae disease incidence and the quality of seedlings raised in seedling boxes and transplanted into pots. The silicate-coated rice seed (SCS) was prepared as follows. Naturally infested rice seeds not previously subjected to any fungicidal treatment were dressed with a mixture of 25% silicic acid at pH 11 and 300-mesh zeolite powder at a ratio of 50 g dry seed - 9 mL silicic acid - 25 g zeolite powder. The following nursery conditions were provided : Early sowing, dense seeding in a glass house with mulching overnight and no artificial heating, which were the ideal conditions for determining the effect on the seed. The nursery plants were evaluated for Gibberella. fujikuroi infection or to determine the recovery to normal growth of infected nursery plants in the Wagner pot. Seedlings emerged 2-3 days earlier for the SCS than they did for the non-SCS control, while damping-off and bakanae disease incidence were remarkably reduced. Specifically, bakanae disease incidence in the SCS was limited to only 7.8% for 80 days after sowing, as compared to 91.6% of the non-SCS control. For the 45-days-old SCS nursery seedlings, the fresh weight was increased by 11% and was two times heavier, with only mild damage compared to that observed for non-SCS. Even after transplanting, SCS treatment contributed to a lower incidence of further infections and possibly to recovery of the seedlings to normal growth as compared to that observed in symptomatic plants in the pot. The active pathogenic macro-conidia and micro-conidia were considerably lower in the soil, root, and seedling sheath base of the SCS. In particular, the underdeveloped macro-conidia with straight oblong shape without intact septum were isolated in the SCS ; this phenotype is likely to be at a comparative etiological disadvantage when compared to that of typical active macro-conidia, which are slightly sickle-shaped with 3-7 intact septa. A active intact conidia with high inoculum potential were rarely observed in the tissue of the seedlings treated only in the SCS. We propose that promising result was likely achieved via inhibition of the development of intact pathogenic conidia, in concert with the aerobic, acidic conditions induced by the physiochemical characteristics associated with the air porosity of zeolite, alkalinity of silicate and the seed husk as a carbon source. In addition, the resistance of the healthy plants to pathogenic conidia was also important factor.

Influence of Blockade of Sympathetic Nervous System, Renin-Angiotensin System, and Vasopressin System on Basal Blood Pressure Levels and on Pressor Response to Norepinephrine, Angiotensin II, and Vasopressin (교감신경계, Renin-Angiotensin계, Vasopressin계의 차단이 혈압 및 Norepinephrine, Angiotensin II 및 Vasopressin의 승압효과에 미치는 영향)

  • Chung, Haeng-Nam
    • The Korean Journal of Pharmacology
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    • v.28 no.1
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    • pp.61-74
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    • 1992
  • Influence of the blockade of the three major pressor systems-sympathetic nervous system (SNS), renin-angiotensin system (RAS) and vasopressin system-on the pressor responsiveness to norepinephrine (NE), angiotensin II (AII), and vasopressin (VP) as well as on basal blood pressure (BP) levels was investigated in urethane-anesthetized rabbits. To block the SNS and RAS, chlorisondamine (CS) and pirenzepine (PZ), sympathetic ganglionic blockers, and enalapril (ENAL), an inhibitor of angiotensin converting enzyme, respectively were used. And for suppressing the VP system bremazocine (BREM), a kappa opiate receptor agonist shown to suppress plasma levels of VP, was employed. Each of CS (0.4 mg/kg), ENAL (2 mg/kg), and BREM (0.25 mg/kg) produced almost same levels of steady hypotensive state. The hypotensive effect of BREM was significantly attenuated by desmopressin, a synthetic VP-like analogue, suggesting the hypotension being at least in part due to suppression of plasma levels of VP. CS, ENAL and BREM elicited further fall of the BP which had been lowered by ENAL or BREM, CS or BREM, and CS or ENAL, respectively. The hypotension produced by both CS and PZ together with either of ENAL or BREM was more marked than that produced by the three drugs other than CS. CS potentiated the pressor response not only to NE but to AII and VP. The pressor effect of AII was increased by ENAL and BREM, too. The pressor response to VP was also enhanced by BREM. Blockade of ${\alpha}-adrenergic$ receptors with phentolamine or phenoxybenzamine potentiated the pressor response to AII and that to VP. The results on basal BP levels indicate that the three major pressor systems are all participating in control of BP, but SNS has the greatest potential for supporting BP. The finding that blockade of one of the pressor systems induced enhanced pressor responsiveness to the pressor hormone of that particular system as well as to the pressor hormone(s) of the other systems(s) provides evidence for important interactions among the three major pressor systems.

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The Change of Serum Soluble E-selectin in Kawasaki Disease (가와사끼병에서의 혈청 Soluble E-selectin의 변화)

  • Jeong, Jae-Ho;Cho, Eun-Young;Lim, Jae-Woo;Cheon, Eun-Jeong;Ko, Kyong-Og;Lee, Kyung-Il
    • Clinical and Experimental Pediatrics
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    • v.48 no.5
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    • pp.539-544
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    • 2005
  • Purpose : The aim of this study was to investigate the pathophysiologic role of serum E-selectin, vascular endothelial growth factor(VEGF)-induced cell adhesion mollecule in Kawasaki disease(KD) and to look for the evidence of direct relationship between the plasma levels of soluble E-selectin and the incidence of coronary artery lesion(CAL). Methods : Changes in plasma levels of sE-selectin(n=98) over time were measured by enzyme-linked immunosorbent assay(ELISA) in 23 patients with acute KD and 25 age-matched febrile children. Results : Compared with control values, the peak levels of plasma sE-selectin were significantly elevated($mean{\pm}S.E$. : $22.89{\pm}12.53ng/mL$ vs $10.65{\pm}3.42ng/mL$, P=0.01) in KD. 5 patients with CAL, plasma sE-selectin levels before treatment were higher than in 18 patients without CAL($mean{\pm}S.E$. : $39.43{\pm}15.08ng/mL$ and $19.00{\pm}8.32ng/mL$, respectively; P=0.01). Plasma sE-selectin declined rapidly in the majority of KD patients regardless of the presence of CAL. Plasma sE-selectin levels after treatment and convalesent period were similar in KD patients with and without CAL. The plasma levels sE-selectin were correlated with those of white blood cell count(r=0.299, P<0.05), CRP(r=0.430, P<0.05), serum albumin(r=-0.483, P<0.05), serum protein(r=-0.502, P<0.05) and hemoglobin(r=-0.372, P<0.05) not with those of ESR, platelet, or duration of fever. There were significant differences in the initial level of serum sE-selectin between KD with and without CAL($mean{\pm}S.E$. : $39.44{\pm}15.08ng/mL$ vs. $19.00{\pm}17.18ng/mL$) in multivariated linear tests. Conclusion : Plasma sE-selectin levels were significantly higher in KD than in other febrile illness. Higher plamsa levels of sE-selectin may have potential as a predictor of CAL in patients with KD.

Comparison of Paraquat Actions on Oxygen Radical Generation and Lipid Peroxidation between Submitochondrial Particle and Microsome of Mouse Liver (Paraquat에 의한 산소 Radical 생성 및 지질과산화 작용의 Mouse 간 Submitochondria Particle과 Microsome에서의 비교)

  • Choi, Jung-Hwan;Kim, Yong-Sik;Park, Jong-Hwan;Chung, Myung-Hee;Yunn, Chong-Ku
    • The Korean Journal of Pharmacology
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    • v.27 no.2
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    • pp.155-166
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    • 1991
  • In order to evaluate a potential role of mitochondria in the mediation of toxicity of paraquat (PQ), submitochondrial particle and microsome of mouse liver were compared by oxygen radical generation and lipid peroxidation. With NADH in submitochondrial particle and NADPH in microsome as electron donors, PQ stimulated production of superoxide anion and $H_2O_2$ in both fractions. Under the same conditions, PQ enhanced the generation of ethylene from methional suggestiong stimulation of OH production by PQ. But these effects by PQ were somewhat lower in submitochondrial particle than in microsome. In addition, lipid peroxidation(measured as MDA production) was stimulated by PQ in both fractions. The stimulation of lipid peroxidation in both fractions seemed to occur by the same mechanism probably through perferryl ion. This was supported by the following findings: i) The lipid peroxidation in both fractions was partially inhibited by SOD and completely inhibited by DETAPAC(an iron chelator) but not by catalase or OH scavenger. ii) Addition of $ADP-Fe^{3+}$ further increased PQ-induced lipid peroxidation but decreased ethylene production from methional suggesting no correlation between OH production and lipid peroxidation. The redox-cycling of PQ in mitochondria appeared to be linked to NADH dehydrogenase, not to CoQ since all of the observed stimulations by PQ in submitochondrial particle were inhibited by p-hydroxymercuribenzoate(a NADH dehydrogenase inhibitor) but not affected by other respiratory chain blockers. The above results demonstrate that redox-cycling properties of PQ leading to oxygen radical generation and lipid peroxidation can also occur in mitochondria in the same manner as in microsome. Therefore, the observed actions of PQ in mitochondria suggest that mitochondria may also contribute to toxicity of this drug in vivo.

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