Cardiac excitation-contraction coupling in the portal hypertensive rat.
Cardiac excitation-contraction coupling in the portal hypertensive rat.
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门脉高压大鼠的心脏兴奋-收缩耦合。
DOI：
10.1152/ajpgi.2000.279.1.g28
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Battarbee,HD
中科院分区：
文献类型：
--
作者：
Zavecz,JH;Bueno,O;Maloney,RE;O'Donnell,JM;Roerig,SC;Battarbee,HD
慢性门静脉狭窄大鼠心脏的基础收缩能力和对β-肾上腺素受体激活的反应受损。在这里，我们报告了门静脉部分结扎对心肌G蛋白表达、β-肾上腺素受体-G蛋白偶联和兴奋-收缩偶联的影响。左、右室收缩功能(dt/dt)降低30-50%，但舒张率(−dt/dt)无明显变化。异丙肾上腺素引起的正性肌力减弱，但ED50无明显变化。−dt/dt的浓度依赖性增加不受影响。门静脉狭窄对GSα和Giα的表达、霍乱毒素和百日咳毒素诱导的腺苷二磷酸核糖化以及激动剂受体Gs复合体的形成没有影响。在所检测的内皮细胞成分中，咖啡因敏感的肌浆网钙池减少了35%，但钙的摄取和释放过程没有改变；L型钙通道的表观密度降低了60%，亲和力没有变化；二氢吡啶钙通道激动剂Bay K8644引起的dt/dt的相对变化与两组相似，提示其余钙通道功能正常；门静脉狭窄组钠/钙交换减少50%。这些数据表明，门静脉狭窄对心肌的影响是ECC改变的结果。
Basal contractility and responses to β-adrenoceptor activation are compromised in hearts from rats with chronic portal vein stenosis. Here we report the effect of partial ligation of the portal vein on myocardial G protein expression, β-adrenoceptor-G protein coupling, and excitation-contraction coupling (ECC). Contractility (dT/dt) was reduced 30–50% in right and left ventricles, but the rate of relaxation (−dT/dt) was unaffected. Isoproterenol-induced positive inotropism was diminished, but there was no difference in ED50. The concentration-dependent increase in −dT/dtwas unaffected. Gsα and Giα expression, cholera toxin- and pertussis toxin-induced ADP-ribosylation, and formation of the agonist-receptor-Gscomplex were unaffected by portal vein stenosis. Of the components of ECC examined, the caffeine-sensitive sarcoplasmic reticulum Ca2+pool was reduced 35%, although the Ca2+uptake and release processes were unchanged; the apparent density of L-type Ca2+channels decreased 60% with no change in affinity; the dihydropyridine Ca2+channel agonist BAY K 8644 produced relative changes in dT/dtthat were similar in both groups, suggesting normal function in the remaining Ca2+channels; and Na+/Ca2+exchange was reduced 50% in the portal vein stenosis group. These data suggest that the effect of portal vein stenosis on the myocardium is the result of alterations to ECC.
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克伦特罗和抗抑郁药物对大鼠大脑皮层β肾上腺素能受体/N蛋白偶联的影响。
DOI：
--
发表时间：
1985
期刊：
The Journal of pharmacology and experimental therapeutics
影响因子：
--
作者：
O'Donnell,JM;Frazer,A
通讯作者：
Frazer,A
激动剂与大鼠大脑中β肾上腺素能受体的相互作用。
DOI：
--
发表时间：
1984
期刊：
The Journal of pharmacology and experimental therapeutics
影响因子：
--
作者：
O'Donnell,JM;Wolfe,BB;Frazer,A
通讯作者：
Frazer,A
大鼠脑提取物中[3H]尼群地平结合的内源调节剂。
DOI：
--
发表时间：
1988
期刊：
The Journal of pharmacology and experimental therapeutics
影响因子：
--
作者：
Ebersole,BJ;Gajary,ZL;Molinoff,PB
通讯作者：
Molinoff,PB
门脉高压大鼠的心脏质膜物理特性和β-肾上腺素能受体功能未改变
影响因子：
13.5
作者：
Zeng;J. Meddings;Sam Lee
通讯作者：
Sam Lee
大鼠门静脉分流术后高胰高血糖素血症和高动力循环。
影响因子：
--
作者：
D. Kravetz;M. Arderiu;J. Bosch;J. Fuster;J. Visa;R. Casamitjana;J. Rodés
通讯作者：
J. Rodés