Basic Research - Neurourology & LUTS/BPH & Others(구연) (E-039) Inhibition of Nerve Injury-Induced Protein 1 (Ninjurin-1) ameliorates bladder Urology, Severance Hospital, Urology, Severance Hospital, Urology, Severance Hospital, Urology, Severance Hospital SANGWOON Kim, Hyung Kyung Sung, Yong Seung Lee, Sang Won Han Background: Nerve injury-induced protein 1, Ninjurin-1 (Ninj1), is known to be involved in neuro-inflammatory processes and vascular function in response to nerve injury. / Objectives: We investigated the efficacy of Ninj1 neutralizing antibody (Ninj1-Ab) for urothelial injury induced by cyclophosphamide (CYP) in rat. / Materials and Methods: Eighteen female Sprague-Dawley rats (200-250g) were randomized into three groups: Group 1, saline injected control; group 2, CYP plus a single intra-peritoneal injection of immunoglobulin G (IgG) (30µg/kg) control antibody, group 3, CYP plus intra-peritoneal injection of Ninj1-Ab (30µg/kg). A cystometry and histological assessments were performed 24 hours and 48 hours after administration of CYP. / Results and Conclusion: During cystometry in CYP-treated rats, significant decreases in intercontraction interval and micturition pressure threshold were demonstrated. Non-voiding contraction was increased with CYP-treatment. Significant increases of intercontraction interval and micturition pressure threshold were elicited by Ninj1-Ab, not by IgG. The expression of Ninj1 was increased in mucosa and lamina propria with CYP-treatment, and decreased in Ninj1-Ab administration. This recovery was accompanied by induction of phosphorylation of Akt and decreased production of reactive oxygen species. These findings suggest that Ninj1-Ab modulate urothelial repair, which ameliorate the increase in intercontraction interval and reduction of non-voiding contraction in rats treated with CYP. keywords : Nerve Injury-Induced Protein, cyclophosphamide induced cystitis, overactive bladder