细胞外液钙浓度对川芎嗪诱发的豚鼠乳头状肌慢反应电位及收缩力的影响

Effects of [Ca￣(2+)]o on Ligustrazine-induced SAP and FC in papillary muscles of guinea pig

采用常规玻璃微电极技术观察了改变细胞外液钙浓度（［Ｃａ２＋］ｏ）对川芎嗪诱发的豚鼠乳头状肌慢反应电位（ＳＡＰ）及收缩力（ＦＣ）的影响。结果：将［Ｃａ２＋］ｏ由０．５、１．０、２．５依次增加到５．０ｍｍｏｌ／Ｌ，ＳＡＰ的幅度（ＡＰＡ）及ＦＣ逐渐加大，并且ＡＰＡ与ｌｇ［Ｃａ２＋］ｏ呈直线关系，［Ｃａ２＋］ｏ增加１０倍，ＡＰＡ约增加２２．０ｍＶ。提示［Ｃａ２＋］ｏ的变化可以影响川芎嗪诱发的慢反应电位的幅度。

Effects of [Ca2+]o on Ligustrazine-induced SAP and FC in the papillary muscles of guinea pig were examined by using standard microelectrode technique.Elevation of [Ca2+]o from 0.5,1.0,and 2.5 to 5.0 mmol/L increased APA of SAP and FC in a dose dependent manner.A linear relationship existed between APA and 1g [Ca2+]o with a slope of 22.0 mV for a 10-fold change in [Ca2+]o.The results suggested that ligustrazine might enhance the slow inward current(Isi) of myocardiac cells.