Responses of the Detrusor Muscle Strips of the Amyda Japonica and the Rabbit to some Autonomic Drugs

Ryu, Soo Bang; Kim, Byung Kap

Abstract

Recent reports suggest that the responses of the detrusor muscle to the hypogastric nerve stimulation and some autonomic drugs may not be identical among various species. In this study, the responses of the isolated detrusor muscle strips of the Amyda Japonica and the rabbit to catecholamines were compared, and the type of the adrenergic-receptors was investigated. The results obtained were as follows : 1. Catecholamines (norepinephrine and epinephrine) evoked only contraction in the isolated detrusor muscle of the Amyda Japonica and relaxation in the preparation of the rabbit. 2. The contraction-response in the Amyda Japonica was blocked in the presence of regitine, an adrenergic alpha-receptor blocking agent. 3. The relaxation-response in the rabbit was abolished by pre-treatment with propranolol, an adrenergic beta-receptor blocking agent. 4. Acetylcholine elicited contraction in both of the isolated detrusor muscle strips of the Amyda japonica and the rabbit, and the response was completely blocked in the presence of atropine. 5. The results described above suggest that catecholamines exert excitatory effect on the detrusor muscle of the Amyda japonica as it contains adrenergic alpha-receptors and inhibitory effect on the same preparation of the rabbit as it contains the adrenergic beta-receptors. Key Word : amyda japonica,alpha receptor, beta receptor.