Ca^(2+) sparks and Ca^(2+) glows in superior cervical ganglion neurons  

作　　者：Li-jun YAO Gang WANG Kun-fu OU-YANG Chao-liang WEI Xian-hua WANG Shi-rong WANG Wei YAO Hong-ping HUANG Jian-hong LUO Cai-hong WU Jie LIU Zhuan ZHOU He-ping CHENG 

机构地区：[1]Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou 310031, China [2]Institute of Molecular Medicine and State Key Laboratory of Biomembrane Engineering, Peking University, Beijing 100871, China

出　　处：《Acta Pharmacologica Sinica》2006年第7期848-852,共5页中国药理学报（英文版）

基　　金：This work was supported by grants from the National Basic Research Program of China(ZZ and HC);the National Natural Science Foundation of China(ZZ,HC,JL,XHW).

摘　　要：Aim： Ca^2＋ release from the endoplasmic reticulum （ER） is an integral component of neuronal Ca^2＋ signaling. The present study is to investigate properties of local Ca^2＋ release events in superior cervical ganglion （SCG） neurons. Methods： Primary cultured SCG neurons were prepared from neonatal rats （P3-P7）. Low concentration of caffeine was used to induce Ca^2＋ release from the ER Ca^2＋ store, and intracellular Ca^2＋ was recorded by high-resolution line scan confocal imaging and the Ca^2＋ indicator Fluo-4. Results： Two populations of local Ca^2＋ release events with distinct temporal characteristics were evoked by 1.5 mmol/L caffeine near the surface membrane in the soma and the neurites of SCG neurons. Brief events similar to classic Ca^2＋ sparks lasted a few hundreds of milliseconds, whereas longlasting events displayed duration up to tens of seconds. Typical somatic and neurite sparks were of 0.3- and 0.52-fold increase in local Fluo-4 fluorescence, respectively. Typical Ca^2＋ glows were brighter （△F/F0 approximately 0.6）, but were highly confined in space. The half maximum of full duration of neurite sparks was much longer than those in the soma （685 vs 381 ms）. Conclusion： Co-existence of Ca^2＋ sparks and Ca^2＋ glows in SCG neurons indicates distinctive local regulation of Ca^2＋ release kinetics. The local Ca^2＋ signals of variable, site-specific temporal length may bear important implications in encoding a ＂memory＂ of the trigger signal.Aim： Ca^2＋ release from the endoplasmic reticulum （ER） is an integral component of neuronal Ca^2＋ signaling. The present study is to investigate properties of local Ca^2＋ release events in superior cervical ganglion （SCG） neurons. Methods： Primary cultured SCG neurons were prepared from neonatal rats （P3-P7）. Low concentration of caffeine was used to induce Ca^2＋ release from the ER Ca^2＋ store, and intracellular Ca^2＋ was recorded by high-resolution line scan confocal imaging and the Ca^2＋ indicator Fluo-4. Results： Two populations of local Ca^2＋ release events with distinct temporal characteristics were evoked by 1.5 mmol/L caffeine near the surface membrane in the soma and the neurites of SCG neurons. Brief events similar to classic Ca^2＋ sparks lasted a few hundreds of milliseconds, whereas longlasting events displayed duration up to tens of seconds. Typical somatic and neurite sparks were of 0.3- and 0.52-fold increase in local Fluo-4 fluorescence, respectively. Typical Ca^2＋ glows were brighter （△F/F0 approximately 0.6）, but were highly confined in space. The half maximum of full duration of neurite sparks was much longer than those in the soma （685 vs 381 ms）. Conclusion： Co-existence of Ca^2＋ sparks and Ca^2＋ glows in SCG neurons indicates distinctive local regulation of Ca^2＋ release kinetics. The local Ca^2＋ signals of variable, site-specific temporal length may bear important implications in encoding a ＂memory＂ of the trigger signal.

关 键 词：superior cervical ganglion neurons Ca^2＋ sparks ryanodine receptors CAFFEINE 

分 类 号：R74[医药卫生—神经病学与精神病学]