Effects of ATP Preparation Myoactin C on the Smooth Muscle

The author has studied the effects of ATP preparation MYOACTIN C on the smooth muscle (small intestine and carotid artery) physiologially. MYOACTIN C is composed of ATP, L-cystine and L-tyrosine, as fix combination drugs. Results of experiments. The author observed that ATP increased the tone of the smooth muscle at a low concentration and decreased it at a high concentration. The effect by L-tyrcsine or L-cystine was faint on the smooth muscle, but L-tyrosine+L-cystine made to fall the tone.Though　some ATP preparatitons on the market showed a remarkable fall of tone strongly and decreased the phasic concentration amplitude. The effects of MYOACTIN C on the smooth muscle can be considered that they relate closely with L-Tyosine+L-cystine. The effects of MYOACTIN C are also investigated at the combined administration of tetrodotoxin (10^-6g/ml), phenoxybenzamin, an adrenargic nerve-blocker (5×10^-6g/ml), pimdolol (2×10^-6g/ml) and also atropin, a cholinergic blocker (5×10^-6g/ml) , respectively