METHODS: Twenty female nulliparous Sprague-Dawley rats of 12 weeks were randomly divided into three groups: 1) uninjured (S; n=6), 2) VD (n=7), and 3) PNI (n=7). Vaginal balloon dilation was performed as previously described. The PNI group underwent transec- tion of both pudendal and iliococcygeus nerves with a combined ventro-dorsal approach. Four days after the injury, rats underwent ST using a chromatographic-filter paper located beneath their grilled-cage. The number of urine spots were calculated under the illumination of ultraviolet light and followed by bladder catheter implantation. A day later, the manual-LPP measurements were performed under urethane (1.2g/kg). All groups underwent US (Visualsonics Vevo 2100, 18-38 mHz) examination to assess the bladder neck and urethra during bladder filling (60 ml/hour) and voiding. The presence, absence and pattern of intraluminal pressure high frequency oscillations (IPHFOs) during the voiding phase were registered. The maximum bladder ca- pacity (ml) and the time needed for urine to leak (sec) from the external urethral meatus were also registered. RESULTS: The LPP in the VD (32.42  2.62 cmH2O) and PNI group (34.61  1.74 cmH2O) were significantly lower than S animals (48.13  3.92 cmH2O; P  0.01). Our US showed the presence of IPHFOs in the S and PNI groups, which was absent in the VD group. The PNI rats showed various patterns of urethral sphincter contraction within an inconsistent interval, while this activity was rhytmic in the S group. Moreover, PNI rats showed a significantly higher number of urine spots than VD and S group (mean 19.7  3.5, 7.5  1.8, and 4.9  1.2 respectively; p = 0.04). No significant differences of BLC and TtL were found between the 3 groups. CONCLUSIONS: Similar to other studies using the LPP meas- urement, we have shown that VD and PNI could simulate SUI in rats. We also showed that US imaging and spot testing are objective parameters that can be determined next to LPP in rat models of SUI. Furthermore, these two novel modalities revealed differences in be- tween SIU models that could not be detected by LPP testing alone. Source of Funding: Departmental Funding 28 MOLECULAR EVIDENCE OF THE NOVEL HCN2 GENE AS NEW DIAGNOSITIC AND TREATMENT FOR INTERSTITIAL CYSTITIS/PAINFUL BLADDER SYDNROME Vikas Tyagi*, Royal Oak, MI; Pradeep Tyagi, Pittsburgh, PA; Jayabalan Nirmal, Samreen Ahmed, Kenneth Peters, Royal Oak, MI; Naoki Yoshimura, Pittsburgh, PA; Michael Chancellor, Royal Oak, MI INTRODUCTION AND OBJECTIVES: It is estimated that be- tween three and eight million women in America are affected by interstitial cystitis/painful bladder syndrome (IC/PBS). HCN2 carry an inward current called Ih that is important for driving the repetitive firing of pain fibers, which make them promising drug target. Recent research has shown that mice which had the HCN2 gene deleted had decreased neuropathic pain. We hypothesize that the pain symptoms suffered by IC/PBS patients may be initiated by HCN2-driven action potential firing in pain-sensitive nerve endings. METHODS: Obtain human bladder biopies from organ donors without urinary problems and patients with urinary symptoms including interstitial cystitis, overactive bladder and incontinence. The detrusor and urothelium was separated by microdissection under sterile condi- tions and stored in RNAlater® solution at 4°C until RNA isolation. Isolated RNA samples from bladder tissues using RNA extraction kits such as RNeasy™ and quantified the extracted RNA using spectro- photometer. Prepared cDNA from 1 g total RNA and performed quantitative Real Time Polymerase Chain Reaction (qPCR) reactions. qPCR amplification was carried out with an initial 10-minute step at 95 °C, followed by 40 cycles at 95 °C for 15 seconds and at 60 °C for 1 minute using a PCR cycler such as Mx3000P® qPCR detection system with fluorescence threshold values calculation by qPCR system soft- ware. -action was used as a reference gene. RESULTS: qPCR analysis of isolated cDNA from human urothelium tissue revealed definite expression of HCN2 was detected. Genomic DNA contamination in RNA samples was ruled out using controls without addition of Reverse Transcriptase cDNA synthesis. CONCLUSIONS: Findings from the present study reveal the identification of increased HCN2 expression in the bladder of Interstitial Cystitis/Painful Bladder Syndrome over normal bladder tissue. HCN2 may play an important role in the pathogenesis of IC/PBS and reveal new mechanism of action and pathophysiology. The HCN2 may pres- ent a new avenue to diagnosis and therapeutic target. In summary, this is a surprising new discovery of a novel gene that is critical for chronic pain and lays the groundwork for the development of new drugs to treat chronic pain by blocking HCN2. In addition, the discovery can lead to new understanding for the underlying mechanism of IC/PBS disease and lead to potential discovery of new method to treat IC/PBS without altering normal urination. Source of Funding: This work was supported in part by a grant from the Tabuman Family Foundation Center of Urological Research in IC 29 DELETION OF FGFR2 FROM TAILBUD-DERIVED STROMA LEADS TO VESICOURETERAL REFLUX, DYSFUNCTIONAL VOIDING, POOR BLADDER COMPLIANCE, AND CHRONIC KIDNEY DISEASE Kenneth Walker*, Irina Zabbarova, Youko Ikeda, Caitlin Schaefer, William Chet de Groat, Anthony Kanai, Carlton Bates, Pittsburgh, PA INTRODUCTION AND OBJECTIVES: During development, tailbud-derived stroma (ST) acts on the Wolffian duct to regulate ureteric bud induction and later forms the smooth muscle of the bladder. Previous data shows deletion of Fgfr2 in ST with Tbx18cre mice (Fgfr2ST-/-) results in vesicoureteral reflux (VUR) in newborn mice likely due to ureteric induction defects. Our aims are to investigate: 1) the natural history of VUR in Fgfr2ST-/- mice; 2) the role of Fgfr2 in bladder muscle development, structure and function, and 3) how bladder defects in the mutants affect renal morphology and function. METHODS: Reflux was assessed by cystograms in euthanized mice. Bladder function was studied by in vivo cystometry and in vitro bladder sheet assays. Tissue morphology was shown by histology and immunohistochemistry. Gene expression was determined by RNA- Seq, qPCR, and in situ hybridization. Renal function was investigated by analyzing urine and serum samples. RESULTS: At 1 month, Fgfr2ST-/- mice had high rates of VUR compared with controls. While bladders from all mice at this age had similar morphology, Fgfr2ST-/- mice had dysfunctional voiding (DV) shown by more frequent and smaller voids. Fgfr2ST-/- mice had higher baseline and threshold bladder pressures and shortened intercontractile intervals than controls. Fgfr2ST-/- mice also have poor compliance, de- creased muscle relaxation and decreased muscle contractility. Gene expression profiles show alterations in collagen isoform and muscle differentiation-associated mRNA in 1 month old Fgfr2ST-/- versus controls. At 6 months, Fgfr2ST-/- mice had high rates of VUR similar to 1 month old mice, often with hydronephrosis. Aged Fgfr2ST-/- mice continued to have DV and develop polyuria. 6 month Fgfr2ST-/- bladders often appear distended with thin, irregular muscle layers as well as increases in type 3 collagen staining compared with controls. Aged Fgfr2ST-/- mice also have signs of chronic kidney disease (CKD) with renal fibrosis, elevated blood urea nitrogen and other biomarkers of injury. CONCLUSIONS: Fgfr2ST-/- mice are a novel genetic model linking VUR and DV with impaired bladder function that together pose a significant risk for CKD. This model suggests a previously unknown requirement for Fgfr2 expression during bladder muscle development, to establish postnatal bladder muscle homeostasis. This model may Vol. 189, No. 4S, Supplement, Saturday, May 4, 2013 THE JOURNAL OF UROLOGY e11