Weiss Dana A, Butler Stephan J, Fesi Joanna, Long Christopher J, Valentino Rita J, Canning Douglas A, Zderic Stephen A
The John W. Duckett Center for Pediatric Urology in the Division of Urology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
The John W. Duckett Center for Pediatric Urology in the Division of Urology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
J Pediatr Urol. 2015 Aug;11(4):188-94. doi: 10.1016/j.jpurol.2015.04.018. Epub 2015 May 27.
To study the pathophysiology of dysfunctional voiding, we have previously developed a model of stress-induced voiding dysfunction. We have shown that cyclosporine A (CsA), an inhibitor of the Ca(2+)-calmodulin complex, can prevent social stress-induced urinary retention. However, treatment with cyclosporine has not had an effect on the increase in the stress peptide corticotrophin-releasing factor (CRF) in Barrington's nucleus, which is involved in the micturition pathway.
We now investigate whether cyclosporine administered after stress can reverse the abnormal voiding phenotype, and whether it has effects on the bladder wall itself, or on the stress response within Barrington's nucleus.
Six-week old Swiss-Webster mice were exposed to aggressor males for 1 h a day, followed by 23 h of barrier separation. In a long-term trial, 1 month of stress was followed by single-cage housing for 6 months. In a separate CsA reversal trial, mice either received CsA in drinking water or had plain drinking water during 1 month of single-cage housing during recovery. Bladder contractile function was examined on a Guth myograph. Nuclear translocation of myocyte enhancing factor (MEF)-2 and NFAT (nuclear factor of activated T cells) in the bladder was assessed using electrophoretic mobility shift assays (EMSAs). The expression of CRF was determined in Barrington's nucleus using in situ hybridization.
Voiding dysfunction persisted for up to 6 months after stress exposure while mice recovered in single-cage housing. In the CsA reversal trial, voiding patterns improved when they received CsA in water during single-cage housing following stress, whereas those that underwent single-cage housing alone had persistent abnormal voiding (Fig. A). There was no difference between CRF levels in Barrington's nucleus between reversal groups (p = 0.42) (Fig. B), possibly indicating a direct effect on the bladder rather than a persistent stress effect. There were no differences in the contractility of bladder wall muscle. CsA decreased the nuclear translocation of MEF-2 and NFAT induced by stress (Fig. C,D).
CsA reverses stress-induced urinary retention, but does not change the stress-induced CRF increase in Barrington's nucleus. Furthermore, bladder smooth muscle contractility is unchanged by CsA; however, there are changes in the levels of the downstream transcription factors MEF-2 and NFAT. We suspect that additional CsA responsive neural changes play a pivotal role in the abnormal voiding phenotype following social stress.
为了研究功能性排尿障碍的病理生理学，我们先前建立了一种应激诱导的排尿功能障碍模型。我们已经表明，钙调蛋白复合物抑制剂环孢素A（CsA）可以预防社会应激诱导的尿潴留。然而，环孢素治疗对参与排尿途径的巴林顿核中应激肽促肾上腺皮质激素释放因子（CRF）的增加没有影响。
我们现在研究应激后给予环孢素是否能逆转异常排尿表型，以及它是否对膀胱壁本身或巴林顿核内的应激反应有影响。
6周龄的瑞士韦伯斯特小鼠每天暴露于具有攻击性的雄性小鼠1小时，然后进行23小时的隔离。在一项长期试验中，应激1个月后单笼饲养6个月。在一项单独的环孢素逆转试验中，小鼠在恢复期间单笼饲养的1个月内，要么饮用含环孢素的水，要么饮用普通饮用水。在Guth肌动描记器上检测膀胱收缩功能。使用电泳迁移率变动分析（EMSA）评估膀胱中肌细胞增强因子（MEF）-2和活化T细胞核因子（NFAT）的核转位。使用原位杂交法在巴林顿核中测定CRF的表达。
应激暴露后，排尿功能障碍持续长达6个月，而小鼠在单笼饲养中恢复。在环孢素逆转试验中，应激后单笼饲养期间饮用含环孢素水的小鼠排尿模式有所改善，而单独进行单笼饲养的小鼠则持续存在异常排尿（图A）。逆转组之间巴林顿核中的CRF水平没有差异（p = 0.42）（图B），这可能表明对膀胱有直接影响，而不是持续的应激效应。膀胱壁肌肉的收缩性没有差异。环孢素降低了应激诱导的MEF-2和NFAT的核转位（图C、D）。
环孢素可逆转应激诱导的尿潴留，但不会改变应激诱导的巴林顿核中CRF的增加。此外，环孢素不会改变膀胱平滑肌的收缩性；然而，下游转录因子MEF-2和NFAT的水平有变化。我们怀疑环孢素反应性的其他神经变化在社会应激后的异常排尿表型中起关键作用。
