TY - JOUR AU - Hu Xiao-Dong AU - Qian Jia-Qing PY - 2016 TI - DDPH inhibited L-type calcium current and sodium current in single ventricular myocyte of guinea pig JF - Acta Pharmacologica Sinica; Vol 22, No 5 (May 2001): Acta Pharmacologica Sinica Y2 - 2016 KW - N2 - Aim: To investigate the effects of 1-(2, 6-dimethylphenoxy)-2-(3,4-dimethoxyphenyl-ethylamino)propane hydrochloride (DDPH) on L-type calcium current (ICa) and sodium current (INa), and to compare its inhibitory potency with verapamil and mexiletine. Methods: Whole-cell patch clamp technique was used to record ICa and INa in a single ventricular myocytes of guinea pig. Results: (1) DDPH (3 - 300 micromol . L-1) decreased ICa at 0 mV in a concentration-dependent manner with an IC50 value of 28.5 micromol . L-1 (95 % confidence limits: 14.3 - 42.7 micromol . L-1, n = 8 cells from 8 guinea pigs). Verapamil (0.3 - 30 micromol . L-1) reduced ICa with an IC50 value of 1.8 micromol . L-1 (95 % confidence limits: 1.3 - 2.3 micromol . L-1, n = 6 cells from 6 guinea pigs). Mexiletine 100 micromol . L-1 did not affect ICa (n = 5 cells from 5 guinea pigs, P > 0.05). The degree of use-dependent blocking effect of DDPH 30 micromol/L on ICa was 58 % +/- 13 % (n = 5 cells from 5 guinea pigs, P 0.05). The blocking effect of DDPH 80 micromol/L on INa was non use-dependent. Conclusion: DPH exhibited inhibitory effects on both ICa and INa, but its inhibitory effect on ICa was weaker than verapamil, and on INa was weaker than mexiletine. UR - http://www.chinaphar.com/article/view/7429