title: A urethral afferent mediated excitatory bladder reflex exists in humans.
abstract: An excitatory reflex between urethral flow receptors and the bladder has been established in animals, but attempts to demonstrate this reflex in humans using urethral fluid flow have been inconclusive. Intraurethral electrical stimulation has recently been shown to generate bladder contractions in animals and was applied to study the presence of an excitatory urethra to bladder reflex in humans. The prostatic urethra was stimulated electrically via a catheter-based electrode in five men with complete spinal cord injury. Bladder contractions were generated in four of five individuals, however, only when the bladder volume was sufficiently large. These results demonstrate the presence of a volume dependent excitatory bladder reflex mediated by urethral afferent nerve fibers and the lumbosacral spinal cord.
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, Wickenden Bldg, Room 108, 10900 Euclid Avenue, Cleveland, OH 44106-4912, USA. kjg@cwru.edu
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Gustafson
authors.forename: Graham H
authors.initials: GH
authors.lastname: Creasey
authors.forename: Warren M
authors.initials: WM
authors.lastname: Grill
mesh_terms: D000328:Adult; D000344:Afferent Pathways / Q000502:physiology; D004558:Electric Stimulation / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D009130:Muscle, Smooth / Q000502:physiology; D012018:Reflex / Q000502:physiology*; D014521:Urethra / Q000502:physiology*; D001743:Urinary Bladder / Q000502:physiology*; D014546:Urinary Catheterization / Q000379:methods