RESUMEN
This study investigated the antispasticity potential of Sativex in mice. Chronic relapsing experimental allergic encephalomyelitis was induced in adult ABH mice resulting in hind limb spasticity development. Vehicle, Sativex, and baclofen (as a positive control) were injected intravenously and the "stiffness" of limbs assessed by the resistance force against hind limb flexion. Vehicle alone caused no significant change in spasticity. Baclofen (5 mg/kg) induced approximately a 40% peak reduction in spasticity. Sativex dose dependently reduced spasticity; 5 mg/kg THC + 5 mg/kg CBD induced approximately a 20% peak reduction; 10 mg/kg THC + 10 mg/kg CBD produced approximately a 40% peak reduction in spasticity. Sativex has the potential to reduce spasticity in an experimental mouse model of multiple sclerosis (MS). Baclofen reduced spasticity and served as a positive control. Sativex (10 mg/kg) was just as effective as baclofen, providing supportive evidence for Sativex use in the treatment of spasticity in MS.
RESUMEN
BACKGROUND: In multiple sclerosis (MS), demyelinating and neurodegenerative lesions develop throughout the central nervous system, which result in a loss of neurotransmission. As a result, people with MS exhibit a wide range of symptoms including dysfunction of the bladder, which can lead to urinary incontinence or retention. Such signs can develop in animal models of MS. Current assessments of bladder properties in animal models are generally invasive, electrophysiological techniques. OBJECTIVE: The use of a non-invasive, ultrasound system for measuring bladder volume in a mouse model of MS. METHODS: Chronic relapsing experimental autoimmune encephalomyelitis was induced in mice. The bladder volume was assessed using ultrasonography, during the disease course and following therapy with bethanechol chloride. RESULTS: It was demonstrated that volumes obtained ultrasonically positively-correlated (r = 0.960) with the urine volumes obtained by manual expression. It was also shown for the first time that bladder size increased significantly in mice with residual neurological deficit. Indeed, this increase in bladder size showed a strong, positive-correlation (r = 0.951) with the hind limb spasticity. Following treatment with bethanechol chloride, bladder volume significantly decreased in mice with chronic experimental autoimmune encephalomyelitis. CONCLUSION: This study demonstrates a novel outcome measure in experimental MS that allows; repeated, non-invasive, high resolution ultrasonic monitoring of bladder function.