Effects of Intravesical Botulinum Toxin-A on Bladder Dysfunction and Autonomic Dysreflexia after Spinal Cord Injury: Role of CGRP Primary Afferents and NGF

Spinal cord injury (SCI) remains a significant cause for morbidity and mortality in North America. Bladder dysfunction following SCI is very common and could lead to severe complications including renal failure and autonomic dysreflexia (AD). AD involves life threatening episodes of hypertension in patients with SCI above T6 level. Current management protocols for AD are symptomatic and usually ineffective. Botulinum toxin-A (BTX-A), has been successfully used recently in SCI patients because it reduces the detrusor contractility via inhibiting acetylcholine release from efferent nerve endings. Recent evidence, however, suggests a sensory involvement via modulation of sensory neuropeptides, neurotransmitters, and receptors. It is still, however, unclear whether BTX-A can affect putative spinal neurons involved in AD. In this study we demonstrated that intravesical BTX-A treatment has blocked AD in rats with T4-SCI, and also provided a novel mechanism for the control of autonomic dysreflexia via a minimally invasive treatment modality.MAS