[The effects of diltiazem on neuromuscular transmission]

The effects of intravenous diltiazem (0.5 and 1.0 mg.kg-1) on muscle compound action potential (CAP) elicited from gastrocnemius muscle by sciatic nerve stimulation in cats were investigated. Analysis was performed on the amplitude of CAP, recovery curve (RC) and train-of-four ratio (TOFR). There was no response in any parameter after administering 0.5 mg.kg-1. On the other hand, diltiazem 1.0 mg.kg-1 produced significant depression only in the amplitude of CAP, but no change was observed in both RC and TOFR. It is concluded that approximately ten times the therapeutic dose of diltiazem is necessary to modify the neuromuscular transmission.