title: Bulbocavernosus reflex during the micturition cycle in normal male subjects.
abstract: BACKGROUND
  To investigate normal changes in the bulbocavernosus reflex (BCR) during the micturition cycle, we examined the change in BCR during the micturition cycle using an evoked potential reaction of the BCR (BCR-EP).
  
  
  METHODS
  Fourteen normal subjects were examined in the study. The BCR-EP was recorded at empty bladder, filled bladder, during voiding and at empty bladder after voiding. To elicit the BCR-EP, the dorsal nerve of the penis was stimulated by two ring electrodes and an electromyogram of the external urethral sphincter was recorded. The maximum amplitude was measured to evaluate changes in the BCR.
  
  
  RESULTS
  The amplitude of the BCR was increased by bladder filling and the ratio of the amplitude at filled bladder/amplitude at empty bladder was 1.32 +/- 0.39. The stable BCR-EP elicited by stimulation at empty bladder disappeared during voluntary voiding in 13 of 14 subjects. However, as stimulation was increased in seven subjects, the BCR-EP was again seen clearly.
  
  
  CONCLUSIONS
  The BCR varies during the micturition cycle, although in normal subjects this variation occurs within a relatively narrow range. Changes in the BCR out of the normal range (e.g. large acceleration by bladder filling or insufficient inhibition during voiding) could suggest the existence of neurogenic disease.
authors.affiliation: Department of Urology, Tohoku University School of Medicine, Sendai, Japan. kaiho@uro.med.tohoku.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kaiho
authors.forename: Takashige
authors.initials: T
authors.lastname: Namima
authors.forename: Haruo
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Masataka
authors.initials: M
authors.lastname: Aizawa
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Uchi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ikeda
authors.forename: Akira
authors.initials: A
authors.lastname: Takeuchi
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Arai
mesh_terms: D000328:Adult; D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D010413:Penis / Q000502:physiology*; D012018:Reflex; D014521:Urethra / Q000502:physiology*; D014554:Urination / Q000502:physiology*