Differential changes in phospholipase D and phosphatidate phosphohydrolase activities in ischemia-reperfusion of rat heart
Differential changes in phospholipase D and phosphatidate phosphohydrolase activities in ischemia-reperfusion of rat heart
复制标题
DOI：
10.1016/j.abb.2005.02.002
复制
发表时间：
2005-04-01
影响因子：
3.9
通讯作者：
Tappia, PS
中科院分区：
文献类型：
--
作者：
Asemu, G;Dent, MR;Tappia, PS
磷脂酶D （PLD2）产生磷脂酸（PA），经磷酸水解酶（PAP2）转化为1,2二酰基甘油（DAG）。由于PA和DAG调节Ca2+运动，我们检测了缺血和再灌注（I-R）心脏的肌膜（SL）和肌浆网状（SR）膜中的PLD2和PAP2。虽然缺血30分钟后SL和SR PLD2活性没有变化，但与对照组相比，5分钟再灌注导致SL PLD2活性增加36%，而30分钟再灌注导致SL PLD2活性降低30%。再灌注5分钟后，SR PLD2活性降低（39%），但再灌注30分钟后恢复到对照水平。缺血60 min导致SL和SR PLD2活性降低，表现为V-max降低，K-m值升高，再灌注时无逆转。虽然在缺血和30min再灌注时，SL PAP2活性降低（31%）和30min再灌注时降低（28%），但SR PAP2活性在30min缺血后没有变化，但在5min再灌注后降低（25(V,)）， 30min再灌注后几乎完全恢复。缺血后再灌注60 min，可引起SL和SR PAP2活性的不可逆抑制。我们的研究结果表明，I-R诱导的心功能障碍与PLD2和PAP2活性的亚细胞变化有关。(c) 2005爱思唯尔公司版权所有。
Phospholipase D (PLD2) produces phosphatidic acid (PA), which is converted to 1,2 diacylglycerol (DAG) by phosphatidate phosphohydrolase (PAP2). Since PA and DAG regulate Ca2+ movements, we examined PLD2 and PAP2 in the sarcolemma (SL) and sarcoplasmic reticular (SR) membranes from hearts Subjected to ischemia and reperfusion (I-R). Although SL and SR PLD2 activities were unaltered after 30 min ischemia, 5 min reperfusion resulted in a 36% increase in SL PLD2 activity, whereas 30 min reperfusion resulted in a 30% decrease in SL PLD2 activity, as compared to the control value. SR PLD2 activity was decreased (39%) after 5 min reperfusion, but returned to control levels after 30 min reperfusion. Ischemia for 60 min resulted in depressed SL and SR PLD2 activities, characterized with reduced V-max and increased K-m values, which were not reversed during reperfusion. Although the SL PAP2 activity was decreased (31%) during ischemia and at 30 min reperfusion (28%), the SR PAP2 activity was unchanged after 30 min ischemia, but was decreased after 5 min reperfusion (25(V,)) and almost completely recovered after 30 min reperfusion. A 60 min period of ischemia followed by reperfusion caused an irreversible depression of SL and SR PAP2 activities. Our results indicate that I-R induced cardiac dysfunction is associated with subcellular changes in PLD2 and PAP2 activities. (c) 2005 Elsevier Inc. All rights reserved.