哇巴因作用下窦房结放电节律的非线性特征  

NONLINEAR CHARACTERS OF FIRING PATTERN FROM SINOATRAL NODE DURING OUABAIN PERFUSION

作　　者：贺书云[1] 菅忠[2] 韩晟[1] 胡三觉[1] 

机构地区：[1]第四军医大学神经科学研究所,西安710032 [2]第四军医大学物理教研室,西安710032

出　　处：《生物物理学报》2003年第4期419-423,共5页Acta Biophysica Sinica

基　　金：国家自然科学基金重点项目(30030040);国家重点基础规划"脑功能和脑重大疾病的基础研究"(G1999054000)项目

摘　　要：运用近似熵及非稳定周期轨道方法,观察哇巴因(ouabain)对大鼠窦房结放电节律的影响,研究窦房结放电节律的非线性动力学特征。 结果显示:应用5 μmol/L ouabain 引起窦房结放电先出现不规则节律后,放电频率增加又转化为规则放电节律,窦房结放电间期由(394±16)ms缩短到(295±13)ms;随后放电节律再次转为不规则,最后窦房结放电间期又转为不规则。窦房结放电间期的近似熵值也随ouabain引起放电节律的不规则程度而增大;应用30μmol/L ouabain时有周期2、3及严重不规则节律的出现,并在严重不规则节律中检测到不稳定周期1、2及3轨道;用40 μmol/L ouabain后则可引起窦性停搏。结果表明ouabain可使窦房结放电序列出现多种节律,其中不规则放电节律含有确定性机制。In order to study the nonlinear characters of firing pattern from sinoatrial node (SA) during ouabain perfusion, ApEn (approximate entropy) and UPOs (unstable periodic orbits) were employed to measure IBI (interbeat interval) from SA firing. The results show that when 5 μmol/L ouabain was applied, IBI became irregular first, then the SA firing frequency accelerated and changed to regular pattern, the IBI decreased from (394±6) ms to (295±13) ms correspondingly; after that the IBI became irregular again; In the end, the IBI changed from regular pattern to a little irregularity. The ApEn varied with the changes of IBI; When sinoatrial node was exposed to 30 μmol/L ouabain, period 2, 3 and irregular rhythm appeared; Among irregular rhythm UPOs (1,2,3) were identified; 40 μmol/L ouabain could stop the firing of sinoatrial node. From above results, It can be concluded that the firing rhythm of SA during ouabain perfusion was based on determinant mechanism.

关 键 词：哇巴因 窦房结 近似熵 不稳定周期轨道 放电节律 

分 类 号：Q424[生物学—神经生物学] Q64[生物学—生理学]