Expression of purinergic P 2 X 2-receptors in neurogenic bladder dysfunction due to spinal cord injury: A preliminary immunohistochemical study

Abstract

Study design:Retrospective descriptive study.Objective:Although muscarinic receptors are the main targets for the treatment of detrusor overactivity today, anticholinergic therapy is not satisfying in a substantial percentage of patients. Recently, overexpression of P 2 X 2 receptors in patients with idiopathic overactive bladder was demonstrated, indicating that purinergic innervation may play an important role in the pathophysiology of detrusor overactivity. We evaluated the expression of P 2 X 2 receptors in patients with spinal cord lesions.Setting:German university hospital.Methods:By immunohistochemical staining, the frequency and intensity of P 2 X 2 expression in bladder specimens from 15 patients with suprasacral spinal cord lesion were compared to those from 11 patients with bladder disorders not related to spinal cord injury (overactive bladder: n6; chronic non-obstructive retention: n2; bladder tumour: n3).Results:Specimens (12/15) from patients with spinal cord lesions and specimens (8/11) without spinal cord lesions demonstrated staining for P 2 X 2 receptors in the detrusor muscle and the urothelium. There was a tendency towards a stronger staining in specimens from patients with spinal cord lesion.Conclusion:Our pilot study gives a first hint that the P 2 X 2 expression in patients with suprasacral spinal cord injury seems to be comparable to the expression in patients with idiopathic overactive bladder. Therefore, P 2 X 2 receptors in detrusor tissue may be a future target for the treatment of detrusor overactivity. © 2009 International Spinal Cord Society All rights reserved.