Department of Psychology, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.
J Urol. 2009 Jul;182(1):337-42. doi: 10.1016/j.juro.2009.02.107. Epub 2009 May 17.
We determined whether clinical observations of hypersensitivity to ice water testing, that is infusion of ice-cold saline into the bladder, in patients with painful bladder syndrome/interstitial cystitis have a parallel in a rat model of bladder hypersensitivity produced by neonatal inflammation.
Rat pups were anesthetized as neonates (postnatal days 14 to 16). In some pups the bladder was inflamed by intravesical zymosan treatment. As adults, the rats were re-anesthetized and tested for abdominal muscle contractions to ice water testing, measured on electromyogram. Various neonatally treated groups of rats underwent bladder re-inflammation/no re-inflammation and/or bladder distention before ice water testing. Other control rats were treated only in adulthood.
Rats that underwent bladder inflammation as neonates manifested bladder hypersensitivity in adulthood, as indexed by significantly greater mean electromyogram responses during ice water testing. This bladder hypersensitivity did not require adult re-inflammation to manifest. Hypersensitivity was also observed with or without prior bladder distention, although the magnitude of electromyogram responses during ice water testing significantly correlated with the magnitude of electromyogram responses to bladder distention. Neonatally induced effects were not significantly related to estrous cycle phase. Exposure to menthol did not significantly enhance the overall magnitude of the electromyogram response to ice water testing in neonatally treated rats.
Current results parallel those in a recent study showing that most patients with painful bladder syndrome/interstitial cystitis experience pain when undergoing ice water testing after previous urodynamic testing. These findings suggest that this animal model may be useful for understanding the etiology of and treatment for painful bladder syndrome/interstitial cystitis.
我们旨在确定在患有疼痛性膀胱综合征/间质性膀胱炎的患者中，冰水试验（将冰冷生理盐水注入膀胱）时出现的过敏临床观察是否与由新生儿炎症引起的膀胱过敏大鼠模型相平行。
在新生期（出生后第 14 至 16 天）对大鼠幼崽进行麻醉。在某些幼崽中，通过膀胱内的几丁质酶处理使膀胱发炎。作为成年人，重新麻醉大鼠并通过肌电图测量对冰水测试的腹部肌肉收缩反应。在进行冰水测试之前，对各种经新生儿处理的膀胱再发炎/无再发炎和/或膀胱扩张的大鼠组进行了处理。其他对照大鼠仅在成年期进行处理。
在新生儿期接受膀胱炎症处理的大鼠在成年时表现出膀胱过敏，其在冰水测试期间的平均肌电图反应明显更大。这种膀胱过敏不需要成年后的再发炎即可表现出来。即使在膀胱扩张之前或之后，也观察到过敏，尽管在冰水测试期间的肌电图反应幅度与膀胱扩张时的肌电图反应幅度显著相关。新生诱导的效应与发情周期阶段无明显相关性。薄荷醇暴露并未显著增强经新生儿处理的大鼠对冰水测试的总体肌电图反应幅度。
当前的结果与最近的一项研究结果相平行，该研究表明，大多数患有疼痛性膀胱综合征/间质性膀胱炎的患者在先前的尿动力学测试后进行冰水测试时会感到疼痛。这些发现表明，该动物模型可能有助于理解疼痛性膀胱综合征/间质性膀胱炎的病因和治疗方法。
