Xu S Z, Zhang Y, Ren J Y, Zhou Z N
Cardiovascular Research Laboratory, Shanghai Xu-hui Central Hospital, China.
Zhongguo Yao Li Xue Bao. 1997 Nov;18(6):515-8.
To study the effects of berberine (Ber) on L-(ICa,L) and T-type (ICa,T) channels in isolated guinea pig ventricular myocytes.
Using whole cell patch-clamp recording technique.
Ber 10, 30 mumol.L-1 inhibited the ICa, L from 1400 +/- 247 pA to 978 +/- 204 pA (n = 5 cells of 5 guinea pigs, P < 0.05), and to 664 +/- 179 pA (n = 5, P < 0.01), respectively. The inhibitory effect was concentration-dependent and non-frequency-dependent. The peak value of ICa,L in the current-voltage relationship was decreased. Ber affected the inactivation kinetics of ICa,L. The half activation potential (V0.5) was shifted from -27.8 mV to -34.2 mV and the slope factor (kappa) was changed from 9.22 into 13.03. Ber did not affect the activation kinetics. Ber 10 and 30 mumol.L-1 also inhibited ICa,T (from 154 +/- 80 pA to 101 +/- 78 pA, and to 48 +/- 45 pA, n = 8 cells of 5 guinea pigs, P < 0.05).
Ber possessed blocking effects on both L- and T-type calcium channels.
研究黄连素(Ber)对豚鼠离体心室肌细胞L型(ICa,L)和T型(ICa,T)钙通道的影响。
采用全细胞膜片钳记录技术。
10、30 μmol·L-1的Ber分别将ICa,L从1400±247 pA抑制至978±204 pA(n = 5只豚鼠的5个细胞,P < 0.05),以及抑制至664±179 pA(n = 5,P < 0.01)。抑制作用呈浓度依赖性且与频率无关。电流-电压关系中ICa,L的峰值降低。Ber影响ICa,L的失活动力学。半数激活电位(V0.5)从-27.8 mV移至-34.2 mV,斜率因子(κ)从9.22变为13.03。Ber不影响激活动力学。10和30 μmol·L-1的Ber也抑制ICa,T(从154±80 pA降至101±78 pA,以及降至48±45 pA,n = 5只豚鼠的8个细胞,P < 0.05)。
Ber对L型和T型钙通道均有阻断作用。