Dolin S J, Hunter A B, Halsey M J, Little H J
Department of Anaesthesia, Addenbrooke's Hospital, Cambridge, U.K.
Eur J Pharmacol. 1988 Jul 26;152(1-2):19-27. doi: 10.1016/0014-2999(88)90831-x.
The effects of the dihydropyridine calcium channel antagonists, nitrendipine and nimodipine, on convulsions produced by different mechanisms have been studied in rats. Nitrendipine and nimodipine significantly raised the thresholds to pentylenetetrazol for up to six hours after their injection. The calcium channel agonist, BAY K 8644, lowered the convulsion threshold to pentylenetetrazol and antagonised the effects of nitrendipine. In contrast, the severity of seizures produced by N-methyl-dl-aspartate (NMA) was increased by nitrendipine. BAY K 8644 also slightly increased the effects of NMA. Nimodipine and nitrendipine caused small, but significant, increases in the threshold pressures for the convulsions caused by raising the atmospheric pressure with helium gas. The compounds had no effect on strychnine convulsions. The conclusion is that the calcium channel antagonists are anticonvulsant against only certain types of convulsions, such as pentylenetetrazol and high pressure (and ethanol withdrawal, reported previously). Others may be increased, such as NMA seizures, or unaffected, such as strychnine-induced convulsions.
在大鼠中研究了二氢吡啶类钙通道拮抗剂尼群地平和尼莫地平对不同机制所致惊厥的影响。尼群地平和尼莫地平在注射后长达6小时显著提高了对戊四氮的惊厥阈值。钙通道激动剂BAY K 8644降低了对戊四氮的惊厥阈值，并拮抗了尼群地平的作用。相反，尼群地平增加了由N-甲基-DL-天冬氨酸（NMA）所致癫痫发作的严重程度。BAY K 8644也轻微增强了NMA的作用。尼莫地平和尼群地平使因用氦气升高大气压所致惊厥的阈值压力有小幅度但显著的升高。这些化合物对士的宁惊厥没有影响。结论是钙通道拮抗剂仅对某些类型的惊厥有抗惊厥作用，如戊四氮和高压（以及先前报道的乙醇戒断）所致惊厥。其他类型的惊厥可能会增加，如NMA所致癫痫发作，或不受影响，如士的宁所致惊厥。
