Intravesical Electromotive Botulinum Toxin-A Administration: an Experimental Study

Abstract

Purpose The method of Intravesical Electromotive Drug Administration (EMDA) has been applied for the treatment of enormous urological pathologies. However, there is no clinical or experimental report of intravesical botulinum toxin-A (BTX-A) administration in the literature. In this study, an animal model was designed to evaluate the depth of BTX-A penetration and its distribution pattern through rabbit bladder wall layers by the application of EMDA. Material and Methods Ten male healthy New Zealand white rabbits were selected, anesthetized and then, catheterized with a specific catheter containing a conducting electrode. The bladder was washed out with normal saline twice or more until the catheter output became clear. The animals were allocated into two groups, the EMDA group (I), a current generator delivered a total of 2 to 2.4 mA at the frequency of 2.5 kHz for 15 min to the fully distended bladder containing 10 IU/kg BTX-A (Dysport®, Ipsen Limited, UK) and two 2 cm × 2 cm dispersive pads, attached bilaterally parallel to midline at the level of distended bladder. In group II, electrical current with same characteristics was applied to the bladder filled with normal saline solution. For each bladder, three full- thickness from dome, posterior and anterior bladder were obtained and submitted for immunohistochemical staining with primary monoclonal antibody in a dilution of 4:100. The negative controls were processed similarly except the primary antibody was eliminated from the protocol. Results Immunohistochemical staining in EMDA group detected BTX-A at the level of eurothelium, interstitial and muscularis layers in the dome, posterior and anterior walls. In control group, all layers were intact. Conclusions In this study, intravesical electromotive BTX-A administration showed deep and homogenous penetration of the toxin throughout the urinary bladder layers.