Issue Archive

Effect of agmatine on intracellular free calcium concentration in isolated rat ventricular myocytes

Li Qing, Shang Zhonglin, Yin Jingxiang, Wang Yihe, He Ruirong

Department of Physiology,Hebei Medical University.Shijiazhuang 050017,Hebei；China；Department of Physiology,Medical College of Chinese People^s Armed Police Forces.Tianjin 300162

Abstract

The results showed that the control level of FI value of single rat ventricular myocytes was 128.8+-13.8 and 119.6+-13.6 in the presence of normal Tyrode^s solution containing Ca~(2+) 1.0 mmol/L and Ca~(2+)-free Tyrode;s solution, respectively. There was no difference between these two groups (P>0.05). Agm 0.1, 1, and 10 mmol/L significantly reduced the [Ca~(2+)]_(i) in both extracellular solutions in a concentration-dependent manner. The similar effect of Agm on [Ca~(2+)]_(i) was also observed in the presence of EGTA 3 mmol/L. KCl 60 mmol/L, PE 30 #mu#mol/L, and Bay-K-8644 10 #mu#mol/L, all these substances induced [Ca~(2+)]_(i) elevations in ventricular myocytes. Agm (0.1, 1, and 10 mmol/L) markedly inhibited the increase in [Ca~(2+)]_(i) induced by KCl, phenylephrine (PE), and Bay-K-8644. When Ca~(2+) waves were produced by increasing extracellular Ca~(2+) concentration from 1 to 10 mmol/L, 1 mmol/L Agm could block the propagating waves of elevated [Ca~(2+)]_(i), and reduce the relocity and duration of propagating waves.

Key words: Agmatine;Fluorescence intensity;Myocytes;Intracellular calcium;Ca~(2+)channel;Intracellular Ca~(2+)release;Confocal microscopy

Received: 　　Accepted:

Corresponding author: 　　E-mail:

Citing This Article：

Li Qing, Shang Zhonglin, Yin Jingxiang, Wang Yihe, He Ruirong. Effect of agmatine on intracellular free calcium concentration in isolated rat ventricular myocytes. Acta Physiol Sin 2002; 54 (6): (in Chinese with English abstract).