Intrathecal Injection of Antispastic Drugs in Rats: Muscle Relaxant Action of Midazolam, Baclofen, 2-Aminophosphonoheptanoic Acid (AP7) and Tizanidine

Spasticity has been defined as a motor disorder characterized by a velocity-sensitive increase in the resistance to passive stretch of muscles, accompanied by exaggerated tendon reflexes. This is thought to result from the hyperexcitability of stretch reflexes as one component of the upper motor neurone syndrome [9, 51]. This definition does not, however, apply to all symptoms and complaints of the upper motor neurone syndrome, for example exaggerated flexor reflexes (flexor spasms), muscle weakness and loss of dexterity.