Ishizawa M, Nitta H, Miyazaki E
Prostaglandins. 1980 Mar;19(3):407-13. doi: 10.1016/0090-6980(80)90074-x.
The effects of lanthanum(La) on contractions induced by prostaglandin F2 alpha(PGF2 alpha) or isotonic K+ were investigated in the isolated stomach muscle of guinea-pig. Low concentrations of La( 0.1-1 microM) inhibited the contraction to PGF2 alpha 1 microM in a dose-dependent manner, without affecting the tonic contraction to isotonic K+. 0.1 and 1 microM La shifted the dose-response curve for PGF2 alpha( 0.001 - 1 microM) to the right and reduced the maximum response. The IC50 of La against PGF2 alpha and K+ were 0.6 microM and 30 microM, respectively. These results support the suggestion that PGF2 alpha -induced contraction in the stomach muscle depends mainly on the intracellular release of sequestered Ca, which would be depleted or immobilized by La.
研究了镧（La）对豚鼠离体胃肌中前列腺素F2α（PGF2α）或等渗钾诱导的收缩的影响。低浓度的La（0.1 - 1微摩尔）以剂量依赖性方式抑制对1微摩尔PGF2α的收缩，而不影响对等渗钾的强直性收缩。0.1和1微摩尔的La使PGF2α（0.001 - 1微摩尔）的剂量反应曲线右移并降低最大反应。La对PGF2α和钾的IC50分别为0.6微摩尔和30微摩尔。这些结果支持以下观点：PGF2α诱导的胃肌收缩主要取决于细胞内储存钙的释放，而La会使其耗尽或固定。
