Bladder dysfunction in mice with experimental autoimmune encephalomyelitis

The vast majority of patients with multiple sclerosis (MS) develop bladder control problems including urgency to urinate, urinary incontinence, frequency of urination, and retention of urine. Over 60% of MS patients show detrusor-sphincter dyssynergia, an abnormality characterized by obstruction of urinary outflow as a result of discoordinated contraction of the urethral sphincter muscle and the bladder detrusor muscle. In the current study we examined bladder function in female SWXJ mice with different defined levels of neurological impairment following induction of experimental autoimmune encephalomyelitis (EAE), an animal model of central nervous system inflammation widely used in MS research. We found that EAE mice develop profound bladder dysfunction characterized by significantly increased micturition frequencies and significantly decreased urine output per micturition. Moreover, we found that the severity of bladder abnormalities in EAE mice was directly related to the severity of clinical EAE and neurologic disability. Our study is the first to show and characterize micturition abnormalities in EAE mice thereby providing a most useful model system for understanding and treating neurogenic bladder.