Change in late sodium current of atrial myocytes in spontaneously hypertensive rats with allocryptopine treatment.

Aim: We aimed to study the effect of allocryptopine (All) on the late sodium current (I) of atrial myocytes in spontaneously hypertensive rats (SHR).

Methods: The enzyme digestion method was used to separate single atrial myocytes from SHR and Wistar-Kyoto (WKY) rats. I was recorded using the patch-clamp technique, and the effect of All was evaluated on the current.

Results: Compared with WKY rat cells, an increase in the I current in SHR myocytes was found. After treatment with 30 µM All, the current densities were markedly decreased; the ratio of I/I of SHR was reduced by 30 µM All. All reduced I by alleviating inactivation of the channel and increasing the window current of the sodium channel. Furthermore, I densities of three SCN5A mutations declined substantially with 30 µM All in a concentration-dependent manner.

Conclusions: The results clearly show that an increase in I in SHR atrial myocytes was inhibited by All derived from Chinese herbal medicine.