BOTULINUM TOXIN TYPE A NORMALIZES ALTERATIONS IN UROTHELIAL ATP AND NO RELEASE CAUSED BY CHRONIC SPINAL CORD INJURY

Vol. 179, No. 4, Supplement, Sunday, May 18, 2008

VLWHVSUHVHQWLQJQHRYDVFXODUIRUPDWLRQHSLWKHOL]DWLRQDQGPXVFOH¿EHUV UHJHQDUDWLRQZHUHLGHQWL¿HGDGMDFHQWWRWKHKRVWEODGGHUDQGLPSODQWHG ureters. No stones were noted in any of the bladders. CONCLUSIONS: In a porcine model, endoscopic and histological observation showed that bilateral ureteral implantation onto %$0*FRXOGHQKDQFHHSLWKHOL]DWLRQRQWKHDFHOOXODUPDWUL[DOORJUDIW7KLV new approach using both host ureter and bladder as potential sources RIYDVFXODUL]DWLRQDQGFHOOXODUFRPSRQHQWVIRU%$0*LQWHJUDWLRQPD\ SURPRWHDIDVWHUDQGPRUHHI¿FLHQWUHJHQHUDWLRQSURFHVVOHDGLQJWR better results in BAMG augmentation cystoplasty. Source of Funding: None

217 THE EFFECT OF BOTULINUM TOXIN A ON CHEMICAL STIMULATION OF RAT DORSAL ROOT GANGLION CELLS W Stuart Reynolds*, Alvaro Lucioni, David E Rapp, Gregory T Bales, Daniel S McGehee. Chicago, IL. INTRODUCTION AND OBJECTIVE: Botulinum toxin A (BnTxA) has previously been demonstrated to modulate sensory nerve activity in animal models. Within the bladder, BnTxA inhibits the neurologic response to stimulation with ATP and capsaicin (CAPS). In this study, we investigated whether BnTxA would inhibit rat dorsal root ganglion (DRG) electrophysiologic responses to chemical stimulation. METHODS: Lumbosacral DRGs (L2-S1) were isolated from DGXOWPDOH6SUDJXH'DZOH\UDWVDJHGGD\V HQ]\PDWLFDOO\DQG manually disassociated, and cultured. BnTxA was administered at time of plating to half the dishes. Whole cell patch clamping was performed 24 hours and 48 hours after plating, and the electrophysiologic responses of BnTxA treated cells to ATP and CAPS were compared to control cells. RESULTS: All cells responded to ATP stimulation, with current densities (pA/pF) for 24h control, 24h BnTxA, 48h control, and 48h BnTxA cells of 29.3±10.6, 23.2±8.3, 19.9±4.2, 23.5±8.7 respectively (p=NS). Cell response to CAPS was more variable, with 7/14 (50%) 24h control cells, 8/13 (62%) 24h BnTxA cells, 13/16 (81%) 48h control cells, and 12/13 (92%) 48h BnTxA cells responding. Current densities (pA/pF) in response to CAPS stimulation for 24h control, 24h BnTxA, 48h control, and 48h BnTxA cells were 51.4±23.2, 16.3±6.5, 62.5±17.1, DQG“UHVSHFWLYHO\$VWURQJEXWQRQVLJQL¿FDQWLQKLELWRU\WUHQG was seen at 24h hours (p=NS), followed by an excitatory trend for BnTxA treated cells at 48h (p=0.006). CONCLUSIONS: BnTxA appears not to have an electrophysiologic effect on cultured DRG cells stimulated by ATP. However, cells stimulated with CAPS may have an initial inhibitory response followed by an excitatory response to BnTxA treatment with prolonged incubation. Further study in needed to elucidate the central effects of BnTxA.Financial funding: none. Source of Funding: None

218 BOTULINUM TOXIN TYPE A NORMALIZES ALTERATIONS IN UROTHELIAL ATP AND NO RELEASE CAUSED BY CHRONIC SPINAL CORD INJURY Christopher P Smith*, David A Gangitano, Alvaro Munoz, Nilson A Salas, Timothy B Boone, K R Aoki, Joseph Francis, George T Somogyi. Houston, TX, and Irvine, CA. INTRODUCTION AND OBJECTIVE: The purpose of this paper was to simultaneously examine changes in urothelial ATP and NO release in normal and spinal cord injured animals as well as in spinal cord injured animals treated with botulinum toxin type A (BoNT-A) and to correlate changes in transmitter release with functional changes in bladder contraction frequency and with efferent nerve function. METHODS: Normal and spinal cord injured rat bladders were injected on day 0 with either vehicle (saline containing bovine serum albumin) or BoNT-A. On day 2, in vitro neurotransmitter release and bladder strip contractility studies as well as in vivo cystometrographic studies were conducted. 5(68/765HVWLQJ$73UHOHDVHZDVVLJQL¿FDQWO\HQKDQFHG following spinal cord injury (i.e. 57% increase, p<0.05) and was unaffected by BoNT-A treatment. SCI increased hypo-osmotic evoked urothelial ATP release by 377% (p<0.05). BoNT-A treatment reduced

THE JOURNAL OF UROLOGY®

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evoked ATP release in SCI bladders by 83% (p<0.05). In contrast, K\SRRVPRWLFVWLPXODWLRQLQGXFHG12UHOHDVHZDVVLJQL¿FDQWO\LQKLELWHG following SCI (i.e. 50%, p<0.05) but recovered in SCI rats treated with BoNT-A (i.e. 195% increase in NO release in SCI-BTX treated rats compared to SCI controls, p<0.01). Changes in urothelial transmitter UHOHDVH FRLQFLGHG ZLWK D VLJQL¿FDQW GHFUHDVH LQ EODGGHU FRQWUDFWLRQ frequency (i.e. 67%, p<0.05) in SCI-BTX rats compared to SCI rats. While no difference was measured between neurally evoked contractile amplitude between SCI and SCI-BTX animals, atropine (1µM) inhibited contractile amplitude to a greater extent (i.e. 76%, p<0.05) in the SCIBTX group compared to the SCI group. &21&/86,216:HK\SRWKHVL]HWKDWDOWHUDWLRQVLQWKHUDWLR of excitatory (i.e. ATP) and inhibitory (i.e. NO) urothelial transmitters promote bladder hyperactivity in rat bladders following SCI that can be reversed, to a large extent, by treatment with BoNT-A. Source of Funding: Allergan, Inc.

219 TETRODOTOXIN-RESISTANT Na+-CHANNEL BLOCKADE BY SMP-986 SUPPRESSES THE ACTIVATION OF BLADDER AFFERENTS Hana Yamane*, Setsuko Yamamoto, Takaaki Yamamoto, Kazuki Matsui, Yoshiki Miura, Mutsuo Taiji, Adrian Sculptoreanu, William C de Groat. Suita, Japan, Osaka, Japan, and Pittsburgh, PA. ,1752'8&7,21$1'2%-(&7,9(%ODGGHU&¿EHUDIIHUHQWV may play a key role in the pathogenesis of bladder hyperactivity. Tetrodotoxin-resistant (TTX-R) Na+-channels are predominant subtypes H[SUHVVHGLQWKH&¿EHUVDQGDUHSUHVXPHGWREHSURPLVLQJWKHUDSHXWLF WDUJHWVIRUGLVHDVHVUHODWHGWREODGGHU&¿EHUDIIHUHQWDFWLYDWLRQVXFK as overactive bladder (OAB) or interstitial cystitis (IC). In this study, we investigated the effects of SMP-986: 1) on TTX-R Na+-current (INa) and action potentials (AP) in rat dorsal root ganglion (DRG) neurons, WRFKDUDFWHUL]HWKHSRWHQWLDORI603DVD1D+-channel blocker and  RQEODGGHUDIIHUHQWDFWLYDWLRQSUHGRPLQDQWO\WKH&¿EHU HYRNHGE\ intravesical prostaglandin E2 (PGE2) infusion in rats. METHODS: TTX-R INa and AP were recorded in the presence of TTX (0.5 µM) in rat small DRG neurons using standard whole cell patch clamp techniques. Bladder afferents were activated by continuous intravesical infusion of PGE2 LQ DQHVWKHWL]HG PDOH 6SUDJXH'DZOH\ rats. The activation of afferents was evaluated by counting the c-fospositive cells in spinal cords (L6-S1) dissected after 2 hours of PGE2 infusion. SMP-986 and anti-muscarinic agents were administered intravenously. RESULTS: SMP-986 (30-300 nM) inhibited the TTX-R INa in a voltage-dependent manner, demonstrating the potent Na+channel blocking action of SMP-986. SMP-986 (30-300 nM) reduced the amplitude and increased the threshold of the TTX-R single AP. )XUWKHUPRUH603Q0 VXSSUHVVHGWKH77;5WRQLF¿ULQJ induced by prolonged current injection, demonstrating the potential of SMP-986 to suppress the excitability of C-type DRG neurons. SMP-986 (1, 3 and 6 mg/kg) reduced the spinal c-fos up-regulation evoked by intravesical PGE2, and at the dose of 6 mg/kg, the number of c-fos positive cells was suppressed to the control level. In contrast, anti-muscarinic agents tolterodine (1 mg/kg) and propiverine (6 mg/kg) had no effects in this model. It is suggested that muscarinic receptor antagonism elicits effects distinct from those of SMP-986 which blocks Na+FKDQQHOVDQGGLUHFWO\LQKLELWV&¿EHUDIIHUHQWDFWLYDWLRQ CONCLUSIONS: SMP-986 which suppressed activation of bladder afferents by blocking TTX-R Na+-channels, may offer a promising, alternative therapeutic option for the treatment of diseases related to bladder afferent activation, such as OAB and IC. Source of Funding: None