摘要
目的观察血小板激活因子(PAF)是否影响心室肌细胞钙离子浓度([Ca^(2+)]i)以及通过哪条信号转导通路起作用。方法采用酶法分离豚鼠心室肌细胞,用PAF刺激细胞;用Fluo-3/AM和共聚焦显微镜观察细胞[Ca^(2+)]i;用2-氨乙基硼酸二苯酯(2-APB)和雷诺定(ryanodine)分别阻断IP3和雷诺定信号通路。全细胞膜片钳技术观察心室肌细胞L型钙电流(ICa-L)。结果无论在有钙还是无钙台氏液,PAF(1pmol·L-1~10nmol·L-1)都能增加心肌细胞[Ca^(2+)]i,其作用能够被2-APB2μmo·lL-1阻断,而不能被雷诺定200μmol·L-1阻断。PAF1nmol·L-1对ICa-L没有明显影响,对照组和实验组电流密度分别为-(11.0±1.9)和-(10.5±1.3)pA·pF-1。结论PAF能增加豚鼠心室肌细胞[Ca^(2+)]i,IP3信号通路可能参与了这一过程。
AIM To observe whether platelet activating factor (PAF) will influence cytosolic calcium concentration ( [ Ca^2 + ]i) in ventricular myocytes and which signaling pathway is involoved. METHODS Ventricular myocytes were isolated enzymatically. Cells were stimulated with PAF, and [ Ca^2+ ]i was measured with calcium indicator Fluo-3/AM and a confocal laser microscope. For the observation of signaling channel mediated by inositol 1,4,5-trisphosphate (IP3 ) and ryanodine, 2-aminoethyl diphenylborate ( 2-APB, 2 μmol· L^ - 1 ) and ryanodine (200 μmol· L^- 1 ) were used respectively for blocking the signaling channel. Whole-cell patch clamp was used to study the effect of PAF on L-type calcium channel (ICa-L). RESULTS PAF (1 pmol·L^-1 - 10 nmol·L^-1 ) increased [Ca^2+ ]i in Tyrode's solution with or without calcium, and the APB, but not by effect was inhibited by 2- ryanodine. ICa-L was not changed by PAF 1 nmol· L^ -1 [- ( 11.0 ± 1.9 ) vs - (10.5 ±1.3) pA·pF ^-1]. CONCLUSION Increasing [ Ca^2+ ]i of cardiomyocytes induced by PAF is associated with IP3 pathway, but has nothing to do with ICa-L and ryanodine pathway.
出处
《中国药理学与毒理学杂志》
CAS
CSCD
北大核心
2006年第1期48-52,共5页
Chinese Journal of Pharmacology and Toxicology
基金
国家自然科学基金资助项目(30430780)~~
关键词
血小板激活因子
信号传导
心肌
钙
细胞内
2-氨乙基硼酸二苯酯
肌醇1
4
5-三磷酸
膜片钳技术
全细胞
platelet activating factor
signaltransduction
myocardium
calcium, cytosolic
2-aminoethyl diphenylborinate
inositol 1,4,5-trisphosphate
patch clamp technique, wholecell