Detrusor properties in myelomeningocele patients: In vitro study

Purpose: To characterize detrusor properties of myelomeningocele (MMC) bladders which failed conventional therapy. Materials and Methods: Bladder strips from five end-stage MMC patients were compared with those from five patients with vesicoureteric reflux. The active and passive properties of the detrusor muscles and the effect of different blocking agents on the transmural nerve stimulation were studied. Results: A significant decrease in contractility (p = 0.003) and increased rigidity (p = 0.019) was found in MMC group. In the control group, atropine blocked 77.7% of the detrusor contractility and tetrodotoxin demonstrated an equal blocking effect. In MMC group, atropine blocked 58.2% and tetrodotoxin blocked 77.4% of the detrusor contractility. Conclusion: MMC bladders showed decreased contractility and increased rigidity. In MMC group, the atropine-resistant component which is blocked by tetrodotoxin signifies the possible existence of non-adrenergic, non-cholinergic neurotransmitters (NANC). Further studies are needed to possibly improve the pharmacological therapy of the myelomeningocele detrusor.