2-Aminothiazoline(2-AT)の骨格筋に対する作用様式の解明

抄録

The Effects of 2-amino-2-thiazoline hydrobromide (2-AT) on several skeletal muscle preparations were examined, and the following results were obtained. 2-Amino-2-thiazoline hydrobromide (2-AT) blocked neuromuscular transmission in the sciatic-sartorius of the frog and in the phrenic-diaphragm of the rat followed by an initial facilitation of the twitch ; this block was not antagonized by cholinesterase inhibitors such as neostigmine. In chicks, intravenous injection of 2-AT produced a spastic paralysis resemble that of depolarizing agents and in gastrocnemius preparations of hen, close arterial administration of 2-AT gave a contracture. Close arterial administration of 2-AT on tibialis anterior preparation of the cat produced a block of the neuromuscular transmission elicited by electrical stimulation of the sciatic nerve ; this block was not antagonized by neostigmine as in the case of diaphragm. The neuromuscular block produced by d-tubocurarine was recovered by 2-AT and vice versa. Furthermore no fall in tension occurs during the tetanic stimulation. From the results mentioned above it might be concluded that 2-AT was a depolarizing neuromuscular b1ocking agent and that its potency was one hundredth that of decamethonium bromide in the phrenic-diaphragm preparation of the rat.