Objective To evaluate the fetal cardiac function in gestational diabetes mellitus （GDM） pregnancies under different maternal glycemic controls. Methods Forty four GDM mothers received 78 fetal echocardiographic eval...Objective To evaluate the fetal cardiac function in gestational diabetes mellitus （GDM） pregnancies under different maternal glycemic controls. Methods Forty four GDM mothers received 78 fetal echocardiographic evaluations at three gestational periods （〈28, 28-34 and ≥34 weeks） and were divided into poorly-（DM1） and well-（DM2） controlled groups according to their glycemic control at examination. Seventy uncomplicated mothers were selected as controls. Parameters of fetal cardiac anatomy and function were measured and analyzed. Results GDM fetuses＇ cardiac ventricular walls were thicker than controls＇, and the differences between DM1 and DM2 were not significant except for end-diastolic left ventricular walls. In both GDM groups, the aortic flow velocities increased earlier than pulmonary artery and DM1 fetuses changed earlier than DM2 ones. GDM fetuses＇ left atrial shortening fraction was smaller than the controls＇ in the period of ≥34 weeks and negatively correlated with thicknesses of left ventricular walls and interventricular septum in DM1 fetuses （r=-0.438 and -0.506）. The right ventricular diastolic function in DM1 and DM2 fetuses decreased after the period of 28-34 weeks and in the period of ≥34 weeks respectively. Tel index of both left and right ventricles increased in DM1 group after the period of 〈28 weeks and in DM2 group only in the period of ≥ 34 weeks, with no significant differences between DM1 and DM2 groups in this period. Conclusion Fetuses of GDM mothers showed cardiac function impairments. Good maternal glycemic control may delay the impairments, but cannot reduce the degree. Some cardiac changes in GDM fetuses were similar to those in pregestational diabetic pregnancies except for several parameters and their changing time.展开更多
Zinc is a trace element involved in maintaining cellular structure and function.Although zinc is associated with left ventricular hypertrophy(LVH),there have been few reports on this association.This study aimed to ev...Zinc is a trace element involved in maintaining cellular structure and function.Although zinc is associated with left ventricular hypertrophy(LVH),there have been few reports on this association.This study aimed to evaluate the correlation between Zip14 and expression of endoplasmic reticulum stress(ERS)associated molecules in hypertrophied hearts of rats.Dahl salt-sensitive rats were fed a high salt diet to establish a left ventricular hypertrophy(LVH)rat model.RT-PCR was used to determine Zip14,activating transcription factor(ATF4),ATF6,x-box-binding protein 1(xBP1),C/EBP homologous protein(CHOP),immunoglobulin-binding protein(BiP)mRNA expression.Western blotting was used to evaluate Zip14,BiP,CHOP,GAPDH expression.Zinc levels were measured by Inductively Coupled Plasma Optical Emission Spectroscopy.The results indicated that compared with the Control group,Zip14 mRNA and protein expression in LVH rat hearts were markedly increased(P<0.01).Zinc content in rat heart tissue was significantly increased in the LVH group compared with the Control group(P<0.05).ATF4,ATF6,xBP1 mRNA expressions were increased in LVH rat hearts compared with Control hearts(P<0.001).Compared with the Control group,CHOP and BiP mRNA and protein expression were markedly increased in LVH rat hearts(P<0.05,P<0.01).Linear regression models showed that Zip14 mRNA expressions were positively correlated with zinc concentration,ATF4 and ATF6 mRNA expressions in Control hearts(P=0.0005,P=0.0052,P=0.0026,respectively)and LVH rat hearts(P<0.0001,P=0.0119,P=0.0033,respectively).In conclusion,upregulation of Zip14 in LVH rat hearts correlated with zinc accumulation and induction of ERS.展开更多
"Since childhood, my hometown had been suffering power outages. Later I went to China to study hydropower. After graduation, I came to work at the Nam Phay Hydropower Station built by China North Industries Corpo..."Since childhood, my hometown had been suffering power outages. Later I went to China to study hydropower. After graduation, I came to work at the Nam Phay Hydropower Station built by China North Industries Corporation (NORINCO), and witnessed tremendous changes in my hometown,” said Xaysee, a young man from Laos. This is an example of the change brought by the Belt and Road Initiative to the partner countries, the epitome of strengthening people-to-people ties.展开更多
Cu Jianfen,a notedChinese composer,has written manysongs covering many topics.Her songs are easy to under-stand and sing and are verypopular.It is fair to say thather songs are both artisticpop songs and popular artso...Cu Jianfen,a notedChinese composer,has written manysongs covering many topics.Her songs are easy to under-stand and sing and are verypopular.It is fair to say thather songs are both artisticpop songs and popular artsongs,and that that is thegoal of her career.Gu has written about 800songs for Chinese singersand audiences in the past10 years,revealing both herpassion for composing andher diligent work ethic.Hersongs are especially lovedby young people,and she iswell Known as “an intimatefriend of young people”inChina.One of her earlysongs,“Let Us YoungFriends Meet,”struck achord in the hearts of youngpeople and made a stir展开更多
In any case, it shows that over thousands of hundreds of years, the inseparable connection between human beings and the sea has been generating enormous curiosity, yearning, romances and ardors. Even for someone who w...In any case, it shows that over thousands of hundreds of years, the inseparable connection between human beings and the sea has been generating enormous curiosity, yearning, romances and ardors. Even for someone who was brought展开更多
At the time marking the 40th anniversary of the normalization of Japan-China diplomatic relationship the public show of Hiroshima Kagura was successfully staged in China. As the sponsor on the Japanese side, first of ...At the time marking the 40th anniversary of the normalization of Japan-China diplomatic relationship the public show of Hiroshima Kagura was successfully staged in China. As the sponsor on the Japanese side, first of all, I would like to express展开更多
Distinguished Guests,Ladies and gentlemen,Dear friends,Good afternoon.Let me begin by extending my warmest welcome to all of you to this thematic session on peopleto-people connectivity on behalf of the International ...Distinguished Guests,Ladies and gentlemen,Dear friends,Good afternoon.Let me begin by extending my warmest welcome to all of you to this thematic session on peopleto-people connectivity on behalf of the International Department of the CPC Central Committee,the organizer of this event.Thanks to the concerted efforts展开更多
To assess whether diazoxide could enhance myocardial protection during hypothermic preservation of the rat heart.Methods Langendorff model of isolated rat heart was used.After 30 minutes stabilization,the hearts were ...To assess whether diazoxide could enhance myocardial protection during hypothermic preservation of the rat heart.Methods Langendorff model of isolated rat heart was used.After 30 minutes stabilization,the hearts were stored in 4 ℃ Celsior cardioplegia solution or Celsior solution containing mitoK ATP opener diazoxide (30 μmol/L) with or without mitoK ATP blocker 5-hydroxydecanoate (5-HD,100 μmol/L) for 3,5 or 10 hours followed by 60 minutes reperfusion.The recovery of cardiac function,myocardial enzyme leakage in the coronary effluent and myocardial water content were observed.The myocardial ultrastructure was also determined.Results (1) Diazoxide improved the recovery percent age of left ventricular developed pressure and ± dp/dt max .Moreover,left ventricular end-diastolic pressure was significantly lower in dizoxide treated hearts than hearts in control group after cold preservation for 5,10 hours,respectively.(2) Compared with the preservation in Celsior solution only,the myocardial enzyme leakage in the coronary effluent was significantly reduced in diazoxide groups.(3) Diazoxide significantly decreased the water content of myocardium and increased coronary flow of the hearts compared to control rat hearts.(4) The cardiac effects of diazoxide were attenuated by 5-HD.(5) Myocardial ultrastructure injury was alleviated.Conclusion The results suggest that diazoxide could enhance myocardial protection during hypothermic preservation of the rat heart,involving the activation of Mitochondrial ATP-sensitive potassium channel.5 refs,1 fig, 1 tab.展开更多
the global market, Chinese TV dramas have seen more success in Africa than in any other region. A family comedy, A Beautiful Daughter-in-Law Era, which tells the story of a newly married couple coping with meddling i...the global market, Chinese TV dramas have seen more success in Africa than in any other region. A family comedy, A Beautiful Daughter-in-Law Era, which tells the story of a newly married couple coping with meddling in-laws, became a hit in Tanzania after premiering there in 2013.展开更多
PROFESSIONAL ballerina Yu Chuanya sets high standards for herself. After a recent long haul flight from Beijing to Johannesburg, the 25-year-old went straight into intensive rehearsals soon after landing, ignoring the...PROFESSIONAL ballerina Yu Chuanya sets high standards for herself. After a recent long haul flight from Beijing to Johannesburg, the 25-year-old went straight into intensive rehearsals soon after landing, ignoring the effects of jet lag in pursuit of her craft. What drove her passion was the unique collaboration on the ballet classic Swan Lake, iointly presented by Joburg Ballet of South Africa and Liaoning Ballet of China.展开更多
The cardioprotective effects of melatonin on recovery of rat donor hearts after 12 h of preservation were investigated. Wistar rats weighing 200 to 250 g ( n =24) were randomly divided into 3 groups. In the non sto...The cardioprotective effects of melatonin on recovery of rat donor hearts after 12 h of preservation were investigated. Wistar rats weighing 200 to 250 g ( n =24) were randomly divided into 3 groups. In the non storage group ( n =8), donor hearts were not stored. In the melatonin group ( n =8), donor hearts were stored in 4 ℃ St. Thomas solution with melatonin (0.1 mmo1/L). In the control group ( n =8), donor hearts were stored in 4 ℃ St. Thomas solution only. The coronary flow (CF), cardiac function, coronary vasodilatory response, creatine kinase (CK) and high energy phosphate levels were measured after the hearts had been preserved for 12 h. Transmission electron microscopy was used to examine the microstructural changes after 12 h of preservation. The recovery of cardiac function and coronary vasodilatory response were significantly improved in the melatonin group ( P <0.01). CK release decreased greatly in the melatonin group ( P <0.01). High energy phosphate levels were significantly better preserved in the melatonin group ( P <0.01). Histological findings were much better in the melatonin group than in the control group. These results suggest that melatonin has cardioprotective effects on the recovery of rat donor hearts after 12 h of preservation.展开更多
Aim Aging is an independent risk factor for heart disease, however the effective intervention has not been found so far. Bone marrow mesenchymal stem cells （BMSCs） have been shown to offer a wide variety of cel- l...Aim Aging is an independent risk factor for heart disease, however the effective intervention has not been found so far. Bone marrow mesenchymal stem cells （BMSCs） have been shown to offer a wide variety of cel- lular functions including the protective effects on damaged hearts. Here we investigated the antiaging properties of BMSCs and the underlying mechanism in a cellular model of cardiomyocyte senescence and a rat model of aging hearts. Methods In vitro study, neonatal rat ventricular cells （NRVCs） and BMSCs were cocultured in the same dish with a semipermeable membrane to separate the two populations. In vivo, the BMSCs were injected into the rat hearts to observe their antiaging effects. The expression of β-galactosidase and aging-related proteins, and the lev- els of oxidative stress were determined in vivo and in vitro. The heart function was measured by the High-Resolution Imaging System. Results Monocultured NRVCs displayed the senescence-associated phenotypes, characterized by an increase in the number of β-galaetosidase-positive cells and decreases in the degradation and disappearance of cellular organelles in a time-dependent manner. The levels of reactive oxygen species and malondialdehyde were el- evated, whereas the activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase were de- creased, along with upregulation of p53, p21cipl/wafl and p16INK4a in the aging eardiomyoeytes. These deleterious alterations were abrogated in aging NRVCs cocultured with BMSCs. Qualitatively, the same senescent phenotypes were consistently observed in aging rat hearts. Notably, BMSC transplantation significantly prevented these detri- mental alterations and improved the impaired cardiac function in the aging rats. Conclusions BMSCs possess strong antiseneseence action on the aging NRVCs and hearts and can improve cardiac function after transplantation in aging rats. The present study, therefore, provides an alternative approach for the treatment of heart failure in the elderly population.展开更多
objective:To examine the dose-dependent effects of endothelin-1 (ET-1) on both cardiac function and myocardial metabolism. Methods: lsolated working rat hearts were perfused by oxygenated Krebs buffer with 13 C-enric...objective:To examine the dose-dependent effects of endothelin-1 (ET-1) on both cardiac function and myocardial metabolism. Methods: lsolated working rat hearts were perfused by oxygenated Krebs buffer with 13 C-enriched substrates (1. 0 mmol/L [3-13C] lactate and 0. 25 mmol/L [1,2~13C ] acetate) ; ET-1 was added to the perfusate to produce an estimated circulating concentration of 6O pmol/L (ET60) or 600 pmol/L (ET600). Myocardial energy metabolism and substrate utilization were analyzed by multi-nuclear (31P and 13 C) magnetic resonance (NMR) spectroscopy. Meantime, cardiac output (CO), coronary flow (CF) and left ventricular developed pressure (LVDP) were recorded (Millar catheter). Results: CT decreased when ET-1 level enhanced (- 30% for ET60 group and - 42% for ET600 group,Pr0. 05). CO transiently increased above control but fell after 35 min infusion (-4% in ET60 group and - 23% in ET600 group respectively,P <0. 05). LVDP was also decreased at the end of ET per fusions. 31P NMR spectroscopy showed a decrease in cellular phosphorylation potential ([ATP]/[ADP][Pi]) when ET-1 level increased (y= 5. 2303e-2-5. 517le 5x R ~ 2= 0. 885). However, It is interesting that the PCr/ATP ratio decreased only in ET6O group, while in ET6oo group the further decrease of [ATP]/[ADP][Pi] did not company a further decrease in PCr/ATP. This phenomenon may suggest an inhibition of CPK activity under the circumstance of high ET-1 level. 13C NMR spectroscopy showed an ET-1 mediated inhibition on exogenous lactate utilization. Conclusion: (1)En dothelin-1 has either a directly positive inotropic effect on isolated perfused rat hearts or an indirectly negative inotropic effect through reduced coronary flow; (2)High level ET-1 may decrease myocardial phosphorylation potential and inhibit CPK activity as well ; (3)Acetate is a better substrate comparing to lactate for myocardium of the patients with increased systemic ET levels.展开更多
基金supported by the National Natural Science Foundation of China (81001228)National High Technology Research and Development Program of China (863 Program)(2007AA02Z442)
文摘Objective To evaluate the fetal cardiac function in gestational diabetes mellitus （GDM） pregnancies under different maternal glycemic controls. Methods Forty four GDM mothers received 78 fetal echocardiographic evaluations at three gestational periods （〈28, 28-34 and ≥34 weeks） and were divided into poorly-（DM1） and well-（DM2） controlled groups according to their glycemic control at examination. Seventy uncomplicated mothers were selected as controls. Parameters of fetal cardiac anatomy and function were measured and analyzed. Results GDM fetuses＇ cardiac ventricular walls were thicker than controls＇, and the differences between DM1 and DM2 were not significant except for end-diastolic left ventricular walls. In both GDM groups, the aortic flow velocities increased earlier than pulmonary artery and DM1 fetuses changed earlier than DM2 ones. GDM fetuses＇ left atrial shortening fraction was smaller than the controls＇ in the period of ≥34 weeks and negatively correlated with thicknesses of left ventricular walls and interventricular septum in DM1 fetuses （r=-0.438 and -0.506）. The right ventricular diastolic function in DM1 and DM2 fetuses decreased after the period of 28-34 weeks and in the period of ≥34 weeks respectively. Tel index of both left and right ventricles increased in DM1 group after the period of 〈28 weeks and in DM2 group only in the period of ≥ 34 weeks, with no significant differences between DM1 and DM2 groups in this period. Conclusion Fetuses of GDM mothers showed cardiac function impairments. Good maternal glycemic control may delay the impairments, but cannot reduce the degree. Some cardiac changes in GDM fetuses were similar to those in pregestational diabetic pregnancies except for several parameters and their changing time.
基金supported by the key projects of Tianjin Natural Science Foundation(Grant No.17JCZDJC34800).
文摘Zinc is a trace element involved in maintaining cellular structure and function.Although zinc is associated with left ventricular hypertrophy(LVH),there have been few reports on this association.This study aimed to evaluate the correlation between Zip14 and expression of endoplasmic reticulum stress(ERS)associated molecules in hypertrophied hearts of rats.Dahl salt-sensitive rats were fed a high salt diet to establish a left ventricular hypertrophy(LVH)rat model.RT-PCR was used to determine Zip14,activating transcription factor(ATF4),ATF6,x-box-binding protein 1(xBP1),C/EBP homologous protein(CHOP),immunoglobulin-binding protein(BiP)mRNA expression.Western blotting was used to evaluate Zip14,BiP,CHOP,GAPDH expression.Zinc levels were measured by Inductively Coupled Plasma Optical Emission Spectroscopy.The results indicated that compared with the Control group,Zip14 mRNA and protein expression in LVH rat hearts were markedly increased(P<0.01).Zinc content in rat heart tissue was significantly increased in the LVH group compared with the Control group(P<0.05).ATF4,ATF6,xBP1 mRNA expressions were increased in LVH rat hearts compared with Control hearts(P<0.001).Compared with the Control group,CHOP and BiP mRNA and protein expression were markedly increased in LVH rat hearts(P<0.05,P<0.01).Linear regression models showed that Zip14 mRNA expressions were positively correlated with zinc concentration,ATF4 and ATF6 mRNA expressions in Control hearts(P=0.0005,P=0.0052,P=0.0026,respectively)and LVH rat hearts(P<0.0001,P=0.0119,P=0.0033,respectively).In conclusion,upregulation of Zip14 in LVH rat hearts correlated with zinc accumulation and induction of ERS.
文摘"Since childhood, my hometown had been suffering power outages. Later I went to China to study hydropower. After graduation, I came to work at the Nam Phay Hydropower Station built by China North Industries Corporation (NORINCO), and witnessed tremendous changes in my hometown,” said Xaysee, a young man from Laos. This is an example of the change brought by the Belt and Road Initiative to the partner countries, the epitome of strengthening people-to-people ties.
文摘Cu Jianfen,a notedChinese composer,has written manysongs covering many topics.Her songs are easy to under-stand and sing and are verypopular.It is fair to say thather songs are both artisticpop songs and popular artsongs,and that that is thegoal of her career.Gu has written about 800songs for Chinese singersand audiences in the past10 years,revealing both herpassion for composing andher diligent work ethic.Hersongs are especially lovedby young people,and she iswell Known as “an intimatefriend of young people”inChina.One of her earlysongs,“Let Us YoungFriends Meet,”struck achord in the hearts of youngpeople and made a stir
文摘In any case, it shows that over thousands of hundreds of years, the inseparable connection between human beings and the sea has been generating enormous curiosity, yearning, romances and ardors. Even for someone who was brought
文摘At the time marking the 40th anniversary of the normalization of Japan-China diplomatic relationship the public show of Hiroshima Kagura was successfully staged in China. As the sponsor on the Japanese side, first of all, I would like to express
文摘Distinguished Guests,Ladies and gentlemen,Dear friends,Good afternoon.Let me begin by extending my warmest welcome to all of you to this thematic session on peopleto-people connectivity on behalf of the International Department of the CPC Central Committee,the organizer of this event.Thanks to the concerted efforts
文摘To assess whether diazoxide could enhance myocardial protection during hypothermic preservation of the rat heart.Methods Langendorff model of isolated rat heart was used.After 30 minutes stabilization,the hearts were stored in 4 ℃ Celsior cardioplegia solution or Celsior solution containing mitoK ATP opener diazoxide (30 μmol/L) with or without mitoK ATP blocker 5-hydroxydecanoate (5-HD,100 μmol/L) for 3,5 or 10 hours followed by 60 minutes reperfusion.The recovery of cardiac function,myocardial enzyme leakage in the coronary effluent and myocardial water content were observed.The myocardial ultrastructure was also determined.Results (1) Diazoxide improved the recovery percent age of left ventricular developed pressure and ± dp/dt max .Moreover,left ventricular end-diastolic pressure was significantly lower in dizoxide treated hearts than hearts in control group after cold preservation for 5,10 hours,respectively.(2) Compared with the preservation in Celsior solution only,the myocardial enzyme leakage in the coronary effluent was significantly reduced in diazoxide groups.(3) Diazoxide significantly decreased the water content of myocardium and increased coronary flow of the hearts compared to control rat hearts.(4) The cardiac effects of diazoxide were attenuated by 5-HD.(5) Myocardial ultrastructure injury was alleviated.Conclusion The results suggest that diazoxide could enhance myocardial protection during hypothermic preservation of the rat heart,involving the activation of Mitochondrial ATP-sensitive potassium channel.5 refs,1 fig, 1 tab.
文摘the global market, Chinese TV dramas have seen more success in Africa than in any other region. A family comedy, A Beautiful Daughter-in-Law Era, which tells the story of a newly married couple coping with meddling in-laws, became a hit in Tanzania after premiering there in 2013.
文摘PROFESSIONAL ballerina Yu Chuanya sets high standards for herself. After a recent long haul flight from Beijing to Johannesburg, the 25-year-old went straight into intensive rehearsals soon after landing, ignoring the effects of jet lag in pursuit of her craft. What drove her passion was the unique collaboration on the ballet classic Swan Lake, iointly presented by Joburg Ballet of South Africa and Liaoning Ballet of China.
文摘The cardioprotective effects of melatonin on recovery of rat donor hearts after 12 h of preservation were investigated. Wistar rats weighing 200 to 250 g ( n =24) were randomly divided into 3 groups. In the non storage group ( n =8), donor hearts were not stored. In the melatonin group ( n =8), donor hearts were stored in 4 ℃ St. Thomas solution with melatonin (0.1 mmo1/L). In the control group ( n =8), donor hearts were stored in 4 ℃ St. Thomas solution only. The coronary flow (CF), cardiac function, coronary vasodilatory response, creatine kinase (CK) and high energy phosphate levels were measured after the hearts had been preserved for 12 h. Transmission electron microscopy was used to examine the microstructural changes after 12 h of preservation. The recovery of cardiac function and coronary vasodilatory response were significantly improved in the melatonin group ( P <0.01). CK release decreased greatly in the melatonin group ( P <0.01). High energy phosphate levels were significantly better preserved in the melatonin group ( P <0.01). Histological findings were much better in the melatonin group than in the control group. These results suggest that melatonin has cardioprotective effects on the recovery of rat donor hearts after 12 h of preservation.
文摘Aim Aging is an independent risk factor for heart disease, however the effective intervention has not been found so far. Bone marrow mesenchymal stem cells （BMSCs） have been shown to offer a wide variety of cel- lular functions including the protective effects on damaged hearts. Here we investigated the antiaging properties of BMSCs and the underlying mechanism in a cellular model of cardiomyocyte senescence and a rat model of aging hearts. Methods In vitro study, neonatal rat ventricular cells （NRVCs） and BMSCs were cocultured in the same dish with a semipermeable membrane to separate the two populations. In vivo, the BMSCs were injected into the rat hearts to observe their antiaging effects. The expression of β-galactosidase and aging-related proteins, and the lev- els of oxidative stress were determined in vivo and in vitro. The heart function was measured by the High-Resolution Imaging System. Results Monocultured NRVCs displayed the senescence-associated phenotypes, characterized by an increase in the number of β-galaetosidase-positive cells and decreases in the degradation and disappearance of cellular organelles in a time-dependent manner. The levels of reactive oxygen species and malondialdehyde were el- evated, whereas the activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase were de- creased, along with upregulation of p53, p21cipl/wafl and p16INK4a in the aging eardiomyoeytes. These deleterious alterations were abrogated in aging NRVCs cocultured with BMSCs. Qualitatively, the same senescent phenotypes were consistently observed in aging rat hearts. Notably, BMSC transplantation significantly prevented these detri- mental alterations and improved the impaired cardiac function in the aging rats. Conclusions BMSCs possess strong antiseneseence action on the aging NRVCs and hearts and can improve cardiac function after transplantation in aging rats. The present study, therefore, provides an alternative approach for the treatment of heart failure in the elderly population.
文摘objective:To examine the dose-dependent effects of endothelin-1 (ET-1) on both cardiac function and myocardial metabolism. Methods: lsolated working rat hearts were perfused by oxygenated Krebs buffer with 13 C-enriched substrates (1. 0 mmol/L [3-13C] lactate and 0. 25 mmol/L [1,2~13C ] acetate) ; ET-1 was added to the perfusate to produce an estimated circulating concentration of 6O pmol/L (ET60) or 600 pmol/L (ET600). Myocardial energy metabolism and substrate utilization were analyzed by multi-nuclear (31P and 13 C) magnetic resonance (NMR) spectroscopy. Meantime, cardiac output (CO), coronary flow (CF) and left ventricular developed pressure (LVDP) were recorded (Millar catheter). Results: CT decreased when ET-1 level enhanced (- 30% for ET60 group and - 42% for ET600 group,Pr0. 05). CO transiently increased above control but fell after 35 min infusion (-4% in ET60 group and - 23% in ET600 group respectively,P <0. 05). LVDP was also decreased at the end of ET per fusions. 31P NMR spectroscopy showed a decrease in cellular phosphorylation potential ([ATP]/[ADP][Pi]) when ET-1 level increased (y= 5. 2303e-2-5. 517le 5x R ~ 2= 0. 885). However, It is interesting that the PCr/ATP ratio decreased only in ET6O group, while in ET6oo group the further decrease of [ATP]/[ADP][Pi] did not company a further decrease in PCr/ATP. This phenomenon may suggest an inhibition of CPK activity under the circumstance of high ET-1 level. 13C NMR spectroscopy showed an ET-1 mediated inhibition on exogenous lactate utilization. Conclusion: (1)En dothelin-1 has either a directly positive inotropic effect on isolated perfused rat hearts or an indirectly negative inotropic effect through reduced coronary flow; (2)High level ET-1 may decrease myocardial phosphorylation potential and inhibit CPK activity as well ; (3)Acetate is a better substrate comparing to lactate for myocardium of the patients with increased systemic ET levels.
