[Computer analysis of the electromyogram of the external urethral sphincter (author's transl)]

The electromyograms of canine external urethral sphincter were recorded and analysed with microcomputer ATAC 450 (Nihon Koden Co.). Its electromyographic responses to the alpha-blocker (phentolamine) and beta-blocker (propranolol) were not recognized, although, the action potentials of the external sphincter disappeared by administration of suxamethonium and pancuronium. The opinions that alpha-adrenergic system acts dominantly on the external urethral sphincter can not be supported by our data obtained from this study.