地尔硫䓬和镧离子对豚鼠离体平滑肌钾离子收缩的影响。

Effects of diltiazem and lanthanum ion on the potassium contracture of isolated guinea pig smooth muscle.

作者信息

Magaribuchi T, Nakajima H, Kiyomoto A

出版信息

Jpn J Pharmacol. 1977 Jun;27(3):333-9. doi: 10.1254/jjp.27.333.

DOI:10.1254/jjp.27.333

Abstract

Effects of diltiazem on K-induced contracture of the smooth muscle were examined in the isolated taenia coli and stomach strip of the guinea pig. Results were compared with those of lanthanum ion (La(3+)). K-contracture was evoked by isotonic K-Krebs solution. La(3+) inhibited K-contracture of the taenia coli and effects on the phasic response were found to be more remarkable than on the tonic response. After the removal of La(3+), the phasic response almost regained its normal magnitude, whereas the tonic response was significantly augmented. In contrast to the effects of La(3+), diltiazem inhibited the tonic response more markedly than the phasic response in both taenia coli and stomach strip. Inhibition of the phasic response was elicited, in association with decrease in the frequency of spike discharge during rapid depolarization of the membrane. The effects of diltiazem were completely reversed after washing out the compound. It is assumed that although both La(3+) and diltiazem inhibit the transmembrane influx of Ca(2+), additional mechanisms may differ.

摘要

在豚鼠离体结肠带和胃条上研究了地尔硫䓬对钾诱导的平滑肌挛缩的影响。将结果与镧离子（La(3+)）的结果进行了比较。等渗钾- Krebs溶液诱发钾挛缩。La(3+)抑制结肠带的钾挛缩，发现其对相位反应的影响比对紧张性反应的影响更显著。去除La(3+)后，相位反应几乎恢复到正常幅度，而紧张性反应则明显增强。与La(3+)的作用相反，地尔硫䓬在结肠带和胃条中对紧张性反应的抑制比对相位反应更明显。地尔硫䓬引起相位反应的抑制，同时伴随着膜快速去极化期间动作电位发放频率的降低。洗去该化合物后，地尔硫䓬的作用完全逆转。据推测，虽然La(3+)和地尔硫䓬都抑制Ca(2+)的跨膜内流，但其他机制可能不同。