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Abstract Objective: To compare an albumin-bound gadolinium chelate (gadofosveset trisodium) and an extracellular contrast agent (gadobenate dimeglumine), in terms of their effects on myocardial longitudinal (T1) relaxation time and partition coefficient. Materials and Methods: Study subjects underwent two imaging sessions for T1 mapping at 3 tesla with a modified look-locker inversion recovery (MOLLI) pulse sequence to obtain one pre-contrast T1 map and two post-contrast T1 maps (mean 15 and 21 min, respectively). The partition coefficient was calculated as ΔR1myocardium /ΔR1blood , where R1 is 1/T1. Results: A total of 252 myocardial and blood pool T1 values were obtained in 21 healthy subjects. After gadolinium administration, the myocardial T1 was longer for gadofosveset than for gadobenate, the mean difference between the two contrast agents being −7.6 ± 60 ms (p = 0.41). The inverse was true for the blood pool T1, which was longer for gadobenate than for gadofosveset, the mean difference being 56.5 ± 67 ms (p < 0.001). The partition coefficient (λ) was higher for gadobenate than gadofosveset (0.41 vs. 0.33), indicating slower blood pool washout for gadofosveset than for gadobenate. Conclusion: Myocardial T1 times did not differ significantly between gadobenate and gadofosveset. At typical clinical doses of the contrast agents, partition coefficients were significantly lower for the intravascular contrast agent than for the extravascular agent.
Resumo Objetivo: Avaliar o efeito da utilização de um agente de contraste intravascular baseado em gadolínio quelado a albumina (gadofosveset) no tempo T1 e no coeficiente de partição do miocárdio, quando comparado com um agente de contraste extravascular baseado no gadolínio não quelado a albumina (gadobenato). Materiais e Métodos: Os participantes do estudo foram submetidos a dois exames para aquisições do mapeamento T1 em aparelho de 3 tesla. Utilizando uma sequência de pulso modificada - modified look-locker inversion recovery (MOLLI) -, realizou-se uma etapa pré-contraste e duas etapas pós-contraste do mapa T1 (média de 15 e 21 minutos). O coeficiente de partição foi calculado como: ΔR1miocárdio /ΔR1sangue. Resultados: Um total de 252 valores de mapa T1 no miocárdio e no sangue foi obtido em 21 indivíduos saudáveis. Após a administração do meio de contraste, a diferença média do tempo T1 do miocárdio entre os agentes de contraste foi -7,6 ± 60 ms (p = 0,41) (isto é, gadobenato T1 < gadofosveset T1). Já no sangue, a diferença média de tempo T1 foi 56,5 ± 67 ms (p < 0,001) (isto é, gadobenato T1 > gadofosveset T1). O coeficiente de partição foi maior para o gadobenato (λ = 0,41) do que para o gadofosveset (λ = 0,33), refletindo uma eliminação mais lenta do gadofosveset em comparação com o gadobenato. Conclusão: Os tempos T1 do miocárdio não foram significativamente diferentes entre gadobenato e gadofosveset. Os coeficientes de partição foram significativamente mais baixos para o agente de contraste intravascular em comparação com o agente extravascular em doses clínicas típicas de cada contraste.
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Objective To explore the effect of Xinkang Tablets on myocardial apoptosis index,collagen volume fraction and sarcoplasmic reticulum Ca2+-ATPase activity of rats with adriamycin-induced heart failure.Methods The chronic heart failure (CHF) SD rat model was established by intraperitoneal injection of doxorubicin.After successful modeling,the rats with CHF were randomly divided into 5 groups,namely model group,western medicine group,and low-,middle-and high-dose of Chinese medicine groups,10 rats in each group.The rats in the above groups were given intragastric administration of distilled water,22.5 μg/kg of Digoxin mixed suspension,9,18,36 g/kg of XinkangTablets,respectively,in the volume of 10 mL/kg of distilled water dilution,once a day,for 5 continuous weeks.Another the same batch of 10 SD rats were randomly allocated to the sham operation group,and were treated with intragastric administration of the same volume of distilled water.And then the apoptotic rate of myocardial cells was measured by TUNEL method,the collagen volume fraction (CVF) was measured after Masson staining,and the sarcoplasmic reticulum Ca2+-ATPase activity was determined by inorganic phosphate assay.Results Compared with the sham operation group,the apoptotic rate of myocardial cells and CVF in the model group were increased(P ＜ 0.01),indicating that the myocardial remodeling occurred in rats with CHF.Compared with the model Group,the apoptotic rate of western medicine group and three Chinese medicine groups was significantly decreased(P ＜ 0.01),suggesting that Digoxin and Xinkang Tablets can relieve apoptosis to certain extent.The CVF in Digoxin group and middle-and high-dose of Chinese medicine groups were lower than those in the model Group (P＜ 0.05 or P＜ 0.01),indicating that Digoxin and Xinkang Tablets can delay the myocardial fibrosis.Last but not least,the SERCA2a activities in the middle-and high-dose of Chinese medicine groups were higher than those in the model group (P ＜ 0.05 or P ＜ 0.01),suggesting that Xinkang Tablets may relieve myocardial remodeling and improve cardiac function through the regulation of SERCA2a activity.Conclusion Xinkang Tablets decrease the apoptotic rate and myocardial cell volume fraction probably through the regulation of SERCA2a activity,which may play a role in counteracting apoptosis and myocardial fibrosis,and ultimately delay the remodeling of the myocardium.
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Objective To explore the therapeutic mechanism of kidney-reinforcing,blood-activating and phlegmresolving therapy for left ventricular fibrosis of spontaneously hypertensive rats (SHR).Methods Twenty SHR were randomly assigned to Chinese medicine group and model group.Additionally,ten Wistar-Kyoto(WKY) rats served as normal control group.After 12-week prevention,Masson staining method was used to measure the degree of fibrosis of left ventricular myocardial tissues,reverse transcription-polymerase chain reaction(RT-PCR) was used to detect Smad3 mRNA expression,and Western blotting method was used for the detection of Smad3 protein expression.Results The degree of left ventricular fibrosis myocardial tissue in Chinese medicine group was milder than that in the model group,and Samd3 protein and mRNA expression levels in Chinese medicine group were lower than those in the model group (P ＜ 0.05).Conclusion Kidney-reinforcing,blood-activating and phlegmresolving therapy can improve left ventricular fibrosis in SHR by inhibiting Smad3 expression.
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Objective To investigate the mechanism of inhibitor of calpain on hyperglycemia-induced apoptosis in cultured rat cardiomyocyte.Methods Cardiomyocytes were randomly divided into three groups (control,high glucose,and ALLN).MTT assay was used to detect the viability of cultured cardiomyocytes.Laser confocal microscopy was used to observe the mitochondrial permeable transition and membrane potential.The change of Caspase-3 activity in cardiomyocytes was detected by western blot.Results MTT assay showed that,after 72 h of hyperglycemia,the viability of cardiomyocytes was significantly declined (55％ ± 11％),and the viability in the ALLN pretreatment group was (70％ ± 15％) (P ＜0.05).After hyperglycemia,the mitochondrial permeable transition of cardiomyocyte was increased (30％ ± 15％ vs 60％ ± 11％,P ＜0.05),and membrane potential was declined.Hyperglycemia could increase the expression of cleaved capsase-3,while with pretreatment of ALLN the expression of cleaved caspase-3 was downregulation(0.42 ± 0.11 vs 0.21 ±0.12,P ＜0.05).Conclusions The calpain inhibitor can protect cardiomyocytes from apoptosis under the high glucose condition.
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0.05).Left ventricular mass index and the apoptotic rate of cardiac muscle cells were decreased in low-and high-dose herbal medicine groups(P
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Objective To establish the relationship of serum TNF-? and IL-6 contents with myocardial cell apoptosis in the chronic heart failure (CHF)rats,and to explore the therapeutic mechanism of Anxin Granules (AXG)in treating CHF.Methods Fifty female SD rats were randomly divided into five groups:normal control group (A),model group (B),captopril group(C),low-dosage AXG group (D)and high-dosage AXG group (E).CHF models were established by intraperitoneal injection of small-dose of adriamycin,once per week for continuous 6 weeks.Meanwhile,group C was given captopril injection (6.25mgkg-1d-1),and groups D and E received gastric gavage of low-dosage AXG (0.8 gkg-1d-1)and high-dosage AXG (1.6gkg-1d-1)respectively.After 6 weeks of modeling,serum levels of TNF-? and IL-6 of different groups were tested by ELISA,the apoptosis of myocardial cells was tested by TUNEL,and then the apoptosis index(AI)was counted.Results Serum levels of TNF-? and IL-6 were increased in the model group (P