PT  - JOURNAL ARTICLE
AU  - Yamada, K
AU  - Nakayama, S
AU  - Shiotani, T
AU  - Hasegawa, T
AU  - Nabeshima, T
TI  - Possible involvement of the activation of voltage-sensitive calcium channels in the ameliorating effects of nefiracetam on scopolamine-induced impairment of performance in a passive avoidance task.
DP  - 1994 Sep 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 881--892
VI  - 270
IP  - 3
4099  - http://jpet.aspetjournals.org/content/270/3/881.short
4100  - http://jpet.aspetjournals.org/content/270/3/881.full
SO  - J Pharmacol Exp Ther1994 Sep 01; 270
AB  - We investigated the effects of various types of calcium channel antagonists on the amelioration by nefiracetam [N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide, DM-9384] of scopolamine-induced impairment of performance in a passive avoidance task in mice. The reversal of the scopolamine-induced impairment of performance by nefiracetam showed a bell-shaped plot. Both i.p. and i.c.v. injection of L-type calcium channel antagonists such as nifedipine and flunarizine attenuated the ameliorating effects of nefiracetam, although diltiazem had no effect. Neomycin, an N-type calcium channel antagonist, also attenuated these effects of nefiracetam in a dose-dependent manner. Further, LaCl3 but not NiCl2 showed inhibitory effects on the amelioration by nefiracetam. These results suggest that the activation of high-voltage-activated, but not low-voltage-activated, calcium channels is involved in the ameliorating effects of nefiracetam on scopolamine-induced impairment of performance in a passive avoidance task.