显性脊柱裂动物模型膀胱胆碱乙酰转移酶多巴胺β羟化酶和降钙素基因相关肽表达的研究

Expression of choline acetyl transferase, dopamine-β-hydroxylase and calcitonin gene related peptide in rats with spinal bifida aperta

目的显性脊柱裂可导致不同程度的膀胱功能障碍,发病机制不清,该研究旨在探讨胆碱乙酰转移梅(CHAT)、多巴胺β羟化酶(DBH)和降钙素基因相关肽(CGRP)的表达在显性脊柱裂所致神经性膀胱功能障碍发生发展中的意义。方法用维甲酸(RA)致畸Wistar孕鼠,取20d显性脊柱裂胎鼠20只。同时取正常胎鼠20只,行苏木精-伊红和免疫组织化学染色,检测胎鼠膀胱CHAT,DBH和CGRP的表达。结果在正常胎鼠,膀胱由粘膜、粘膜下、肌层和外膜组成,CHAT,DBH和CGRP广泛分布于膀胱壁各层,以粘膜层、肌层和外膜细胞胞浆着色明显,表达强度光密度值(OD值)分别为398±13,378±14和412±25。显性脊柱裂胎鼠膀胱壁变薄,肌层发育差,CHAT,DBH,CGRP的表达明显减少,OD值分别为156±9,32±6和121±11,差异具有统计学意义(P<0.01)。结论显性脊柱裂胎鼠膀胱壁肌层发育差,膀胱CHAT,DBH,CGRP的表达明显减少,可能是导致显性脊柱裂胎鼠出生后膀胱功能障碍的机制之一。

Objective Spinal bifida aperta （SBA） can lead to different degrees of bladder dysfunction, the mechanism is unclear. This paper determined the expression of choline acetyl transferase （CHAT）, dopamine-β- hydroxylase （DBH） and ealcitonin gene related peptide （CGRP） in the urinary bladder in rat embryos with SBA. The goal was to study the role of these genetic expressions in the development of bladder dysfunction. Methods Rat embryos with SBA were generated by an administration of retinoic acid （RA） to pregnant rats, Normal rat embryos （ Control group, n = 20） and rat embryos with SPA （Study group, n = 20） on day 20 of gestation were taken out. The specimens from the bladder were stained with hematoxylin-eosin and immunohistochemistry for the detection of CHAT, DBH and CGRP expression. Results In the Control group, the bladder was composed of mucosa, submucosa, muscle and adventitia, and the immunoreactive nerve fibers of all markers were abundant in various layers of the bladder. In the Study group, the bladder muscle layer of the rat embryos was thin and less abundant. The expressions of CHAT （ 156 ±9）, DBH （32 ±6） and CGRP （ 121 ± 11 ） in the Study group were significantly lower than those in the Control group （398 ± 13,378 ± 14 and 412 ±25, respectively） （P 〈 0, 01 ）. Conclusions The bladder muscles were poorly developed and the expression of CGRP, CHAT and DBH were decreased in the rat embryos with SPA. These changes might contribute to the bladder dysfunction caused by SPA.