Godfraind T, Finet M, Lima J S, Miller R C
J Pharmacol Exp Ther. 1984 Aug;230(2):514-8.
Depolarization (100 mM K+) of acetylcholine, serotonin and prostaglandin (PG) F2 alpha contracted human isolated coronary artery segments. Serotonin was about 10-fold more potent than either acetylcholine or PGF2 alpha, but PGF2 alpha elicited contractions of the greatest magnitude. Serotonin (10 microM) and PGF2 alpha (3 microM) induced rhythmic contractions in the arterial segments. Depolarization-, PGF2 alpha- and serotonin-induced increase in tone was depressed by nifedipine, as was the serotonin- and PGF2 alpha -induced rhythmic activity. The induced rhythmic activity was about 100-fold more sensitive to inhibition by nifedipine than was the induced tonic contraction of the arteries. Depolarization-induced contractions and serotonin-induced rhythmic contractions displayed about equal sensitivity to inhibition by nifedipine. Nifedipine was more potent as an inhibitor of depolarization-induced contractions of arteries than it was as an inhibitor of electrically stimulated trabecular strips of ventricle from the same hearts. The inhibition of isolated coronary artery contraction was obtained within the range of nifedipine concentrations observed in the blood of treated patients.
乙酰胆碱、5-羟色胺和前列腺素（PG）F2α使去极化（100 mM钾离子）的人离体冠状动脉节段收缩。5-羟色胺的效力比乙酰胆碱或PGF2α约强10倍，但PGF2α引起的收缩幅度最大。5-羟色胺（10微摩尔）和PGF2α（3微摩尔）在动脉节段中诱导节律性收缩。硝苯地平可抑制去极化、PGF2α和5-羟色胺诱导的张力增加，以及5-羟色胺和PGF2α诱导的节律性活动。诱导的节律性活动对硝苯地平抑制的敏感性比动脉诱导的强直性收缩约高100倍。去极化诱导的收缩和5-羟色胺诱导的节律性收缩对硝苯地平抑制的敏感性大致相同。硝苯地平作为动脉去极化诱导收缩的抑制剂比作为同一心脏电刺激心室小梁条的抑制剂更有效。在治疗患者血液中观察到的硝苯地平浓度范围内，可抑制离体冠状动脉收缩。
