2026-11-092026-11-09https://scholars.csmu.edu.tw/handle/123456789/38820The bladder-to-urethra and urethra-to-bladder reflexes have been extensively explored to demonstrate the mechanisms for the neural control of micturition. In female rats, contraction of the external urethral sphincter activates afferents that inhibit reflex bladder contractions; whereas infusion of fluid through the urethra facilitates bladder contractions. Both ionotropic N-methyl-D-aspartic acid (NMDA) and α-amino-3-hydroxy-5-methyl- 4-isoxazoleproprionate (AMPA) receptors modulate the micturition reflex pathway. In our previous study, we established a pelvic-pudendal reflex potentiation (long-term potentiation-like reflex in the external urethral sphincter electromyogram activity) model in anesthetized rats. It has also been demonstrated that this pelvic-pudendal reflex potentiation mechanism is mediated by glutamate, through ionotropic NMDA and AMPA receptors directly regulating the opening of ion channels to sodium, potassium and calcium ions via repetitive stimulation. We named this pelvic-spinal-pudendal-urethral reflex, “spinal reflex potentiation”. It is similar to the long-term potentiation which occurs in the CA1 region of the hippocampus or the dorsal horn of the spinal cord. Recently, botulinum A toxin (BTX-A) seems to offer an attractive option for cases of neurogenic and idiopathic detrusor overactivity refractive to anticholinergics and for detrusor sphincter dyssynergia due to spinal cord injury, interstitial cystitis, pelvic pain, benign prostatic hyperplasia and perineal pain. The clinical effects of BTX-A are thought to have three mechanisms of action: blockade of the acetylcholine release at the neuromuscular junction, inhibiting release of other neurotransmitters, and inhibition of afferent neurotransmission acting as an analgesic property. BTX-A can also significantly decrease pain behaviors and reduce the release of pain-signaling mediators 5 hours to 12 days after injection. The antinociceptive effects of BTX seem to be independent of BTX’s effects on the neuromuscular junction. Based on the spinal reflex potentiation rat model which has been developed in my laboratory, we postulate that BTX-A can inhibit or attenuate the potentiation of the EUSE activity through repetitive stimulation of the pelvic nerve trunk. In this proposal, we try to evaluate: 1. Whether BTX-A (via. detrusor injection or intravesical administration) modulates the spinal NMDA mediated pelvic-spinal-pudendal-urethral reflex potentiation. 2. What the dose dependent curve of BTX-A and the frequency dependent curve of repetitive stimulation are if the pelvic-spinal-pudendal-urethral reflex potentiation (spinal reflex potentiation) can be modulated by BTX-A. 3. The expression of C-fos, CGRP, GABA-a, GABA-b, TRPV1 and TRPV2 in the dorsal horn at L6-S1 in rats. 4. Whether BTX-A can modulate the cross-organ interaction of the bladder and the uterus after being treated with capasian.經由電刺激骨盆神經殘幹（遠端已截斷的骨盆神經）， 可在外尿道括約肌上的肌電圖 (Electromyogram) 記錄到反應，此一反應被稱為外尿道括約肌肌電圖活動性(external urethral sphincter electromyogram activity, EUSE activity)。我們將由 ”骨盆神經”經由 “脊髓” 再傳至 “會陰神經”的反射路徑，並可以記錄到 ”外尿道括約肌肌電圖活動性” 的反射， 稱為骨盆神經-脊髓-外尿道括約肌反射 (pelvic-spinal- external urethral sphincter reflex)。我們的實驗室使用低頻率 (1 Hz) 連續刺激 (repetitive stimulation) 骨盆神經殘幹時，於紀錄外尿道括約肌肌電圖活性 (EUSE activity) 時，可以產生增益效應的現象 (Chen 2006)。利用此一模式做為模擬由膀胱的感覺神經引發外尿道括約肌收縮反應的試驗，此一反射反應的模式與過去在大腦和脊髓背角內已被廣泛研究的長期增益現象 (long-term potentiation)類似。我们在 2006年的論文將此一反應塑性 (reflex plasticity) 現象稱為脊髓反射增益作用現象 (spinal reflex potentiation, SRP)。而此一反射路徑我们發現可透過NMDA和 AMPA接受器路徑的調控。 肉毒桿菌毒素 A 被應用於治療下泌尿道的儲尿期與排尿期功能障礙，主要是利用肉毒桿菌毒素 A 的化學去神經作用 (Chemodenervation) 的特性。除了被用於治療泌尿道症狀外，肉毒桿菌毒素A也被証實可減少疼痛訊息傳導物質 (pain-signaling mediators) 在脊髓背角的表現量 (Cui et al. 2004)。此類antinociceptive的作用機轉與它在下泌尿道的作用機轉相類似， 我們推論這類的作用途徑可能與暫時阻斷脊髓背角的長期增益現象有關。 因此，本研究計畫將利用大白鼠實驗的脊髓反射增益效應模式，檢視下列五個研究假設： 一、 肉毒桿菌毒素A注射於膀胱肌肉後，可以減弱連續電刺激所引發的骨盆神 經–脊髓–外尿道括約肌的增益效應現象。 二、 肉毒桿菌毒素A注入膀胱內，也可以減弱連續電刺激所引發的骨盆神 經–脊髓–外尿道括約肌的增益效應現象。 三、 將透過此一種 “活動依賴性的反射塑性 (activity-dependent reflex plasticity) 的模式”，檢測C-fos、 CGRP、 TRPV等訊息傳導因子在脊髓背角的表現量。 四、 檢測肉毒桿菌毒素A劑量與電刺激頻率的關係，即測定肉毒桿菌毒素A與電刺激頻率的濃度效應曲線 (frequency dependent and dose dependent curve)。 五、 檢測肉毒桿菌毒素A是否可以減緩Berkley所提出臟器間的相互作用(Cross-system Viscero-visceral interactions) (Berkey 2005)。我們利用Capasacin處理子宮， 將肉毒桿菌毒素A注射在逼尿肌或注入膀胱內，再利用我們的實驗模式測試。檢測肉毒桿菌毒素A是否可進一步抑制骨盆神經–脊髓–外尿道括約肌的增益效應。 預期本研究計劃的結果，可以被應用於婦女骨盆腔臟器的疼痛及慢性骨盆疼痛的治療。Project