Physiologie de la miction
Michel Perrigot, Bernard Pichon, Jacques Pichon
Kinésithér Scient 2013,539:25-31 - 10/01/2013
Le cycle continence-miction est une succession de réflexes intégrés, sous contrôle de la volonté. La continence, longue, est caractéristique par l'apparition, au cours du remplissage, de la sensation de besoin, phénomène complexe avec codage volumepression, sensitisation des afférents nerveux, rôle de l'urothélium, intégration centrale. La miction est courte, par contraction du détrusor et relaxation de l'urètre, avec un rôle déterminant du centre bulbo-protubérantiel. Le réflexe mictionnel spino-bulbo-spinal est sous le contrôle tonique inhibiteur des structures cortico-diencéphaliques. Les médiateurs chimiques intervenant aux différents niveaux sont mieux connus.
Urination and continence are controlled by a succession of reflexes which are under voluntary control. Continence (which is long), involves the sensation of needing to go to the toilet as the bladder is being filled. This complex phenomenon involves a volume-pressure system, sensitization of nerve afferents, role of the urothelium, central integration. Urination (which is short) is characterized by contraction of the detrusor and relaxation of the urethral sphincter. The urination center in the pons plays an important role. The spino-bulbo-spinal urination reflex is under tonic inhibitor control from higher brain centers. Chemical mediators which are present at different levels are currently not well understood.
Urination and continence are controlled by a succession of reflexes which are under voluntary control. Continence (which is long), involves the sensation of needing to go to the toilet as the bladder is being filled. This complex phenomenon involves a volume-pressure system, sensitization of nerve afferents, role of the urothelium, central integration. Urination (which is short) is characterized by contraction of the detrusor and relaxation of the urethral sphincter. The urination center in the pons plays an important role. The spino-bulbo-spinal urination reflex is under tonic inhibitor control from higher brain centers. Chemical mediators which are present at different levels are currently not well understood.