Format

Send to

Choose Destination
Br J Pharmacol. 1988 Aug;94(4):1250-6.

Inhibitory actions of amoxapine, a tricyclic antidepressant agent, on electrophysiological properties of mammalian isolated cardiac preparations.

Author information

1
1st Department of Internal Medicine, Tottori University, Yonago, Japan.

Abstract

1. The electrophysiological effects of amoxapine were examined in guinea-pig isolated papillary muscles and rabbit sinoatrial nodes using a conventional microelectrode technique. 2. In papillary muscles, amoxapine above 10 microM caused a dose-dependent decrease in the maximum upstroke velocity (Vmax) of the action potential and in the action potential amplitude (APA), whereas the action potential duration at 90% repolarization (APD90) was significantly prolonged. For a decrease in Vmax, amoxapine produced a negative shift of the curve relating Vmax to the resting potential (Em) along the voltage axis to more negative membrane potentials. 3. Amoxapine also decreased Vmax and the overshoot potential of K+-depolarized slow action potentials of papillary muscle preparations. 4. In spontaneously beating sinoatrial node preparations, amoxapine above 3 microM reduced the heart rate, Vmax, APA and the slope of phase 4 depolarization in a dose-dependent manner. 5. It was concluded that amoxapine exerts inhibitory actions on fast- and slow-response fibres of the heart and these actions can be mainly explained by inhibition of both fast Na+ and slow Ca2+ channels.

PMID:
3207983
PMCID:
PMC1854089
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center