Effects of 5-(N,N-diethylamino)-n-pentyl-3,4,5-trimethoxybenzoate hydrochloride (TMB-5) on cardiovascular systems.

The effects of 5-(N,N-diethylamino)-pentyl-3,4,5-trimethoxybenzoate hydrochloride (TMB-5) were studied pharmacologically on smooth muscle, skeletal muscle, blood vessel and cardiac preparations. In all cases, TMB-5 inhibited muscle contractions induced by muscle stimulants such as acetylcholine, norepinephrine, KCl and BaCl2, indicating that the muscle inhibition induced by TMB-5 is unrelated to specific receptors. TMB-5 was found to be most potent in inhibiting skeletal muscles (at 10(-6)-10(-5) M level) and least effective in inhibiting smooth muscles (at 10(-4)-10(-3) M level). The potency of vascular inhibition was in between these two levels (at 10(-4) M level). The ability of TMB-5 to raise the threshold of cardiac arrhythmias was quite good at 7X10(-7)-7X10(-6) M. It is concluded that TMB-5 could be a good antiarrhythmic agent with some skeletal muscle relaxation action.