卵巢激素对慢性内脏高敏感大鼠结肠组织5-HT3受体的影响

目的 在慢性高敏感大鼠模型上构建去卵巢模型，观察大鼠结肠组织5-HT3受体在雌激素不同水平的变化，探讨卵巢激素对IBS发病的影响。方法 选取新生SD雌鼠，在其发育的8．21天给予结直肠球囊扩张刺激，建立慢性内脏高敏感雌鼠模型，待其发育至2月大小将雌鼠随机分为3组：假手术(sham)组、去卵巢(ovx)组、去卵巢加雌激素和孕激素(ovx E2 P)组，每组16只，处理4周后对其内脏敏感性进行行为学评估(AWR评估)，观察各组大鼠玻璃小球排出情况；并采用RT-PCR及免疫组织化学SP法检测大鼠肠道5-HL受体的变化。结果 ovx E2 P组大鼠腹部抬起及拱背抬高压力值明显低于sham组和ovx组；ovx E2 P组大鼠排便量增多，玻璃小球排出时间短于sham组和ovx组；ovx E， P组5-HB受体水平最高，ovx组受体水平最低。结论 卵巢激素促进结肠组织5-HT3受体的表达，加重内脏高敏感性。

Effects of ovarian hormone on 5-HT3 receptors in the rat colon with visceral hypersensitivity

Objective To examine the effects of ovarian hormone on 5-HT3 receptors in the rat colon with visceral hy-persensitivity and investigate the pathogenesis of irritable bowel syndrome in women. Methods Neonatal female Sprague-Daw ley rats received mechanical colonic irritation between postnatal day 8 and 21 and were randomly divided into three groups ( 16/each) when they were 3 months old: shame operation (sham) ,ovariectomy (ovx) and overiectomy with estrogen (E2) and progesterone (P) replacement therapy (ovx E2 P) . The abdominal withdrawal reflex (AWR) were recorded and the fecal habits were observed four weeks after operation. The expression of 5-HT3 receptors were examined by RT- PCR and immunohis-tochemical staining. Results ovx E2 P group rats showed a significant decrease endurance with colonic irritation; ovx E2 P group rats showed increase in fecal pellets and decrease in the time of vitreous pellets excretion; ovx E2 P group rats express significant higher 5-HT3 receptors in colon. Conclusion Ovarian hormone aggravates visceral hypersensitivity in rats and increase 5-HT3 receptors levels in rats colon.