EFFECTS OF 4-AMINOPYRIDINE ON CALCIUM CURRENTS AND SODIUM CURRENTS IN GUINEA PIG VENTRICULAR MYOCYTES
- Author:
- No author available
- Journal Title:
- ACTA PHARMACEUTICA SINICA
- Issue:
- 4
- DOI:
- 10.3321/j.issn:0513-4870.2001.04.003
- Key Word:
- 4-氨基吡啶;心肌细胞;钙电流;钠电流;膜片钳
Abstract： AIM To investigate the effect of 4-aminopyridine (4-AP) on ion channels of myocytes. METHODS L-type calcium channel and sodium channel currents were recorded in guinea pig single ventricular myocyte using whole-cell patch-clamp techniques. RESULTS 4-AP, 0.1, 0.5 and 1.0 mmol*L-1 were shown to inhibit L-type calcium channel currents (ICa,L) and sodium channel currents (INa) concentration-dependently. The percentage of inhibition were (11.6±1.7)%, (37.5±8.3)% and (54.5±6.9)% (P<0.01) respectively for ICa,L, and (22.1±14.3)% (P<0.05), (39.4±8.8)% and (62.3±6.8)% (P<0.01) respectively for INa. 4-AP 0.5 mmol*L-1 shifted the I-V curves of ICa,L and INa upwardly. CONCLUSION 4-AP blocked L-type calcium channel and sodium channels in guinea-pig ventricular myocytes concentration-dependently.
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