Luminally released serotonin stimulates colonic motility and accelerates colonic transit in rats.
Luminally released serotonin stimulates colonic motility and accelerates colonic transit in rats.
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腔内释放的血清素刺激结肠运动并加速大鼠的结肠转运。
DOI：
10.1152/ajpregu.00856.2006
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Takahashi,Toku
中科院分区：
文献类型：
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作者：
Tsukamoto,Kiyoshi;Ariga,Hajime;Mantyh,Chris;Pappas,TheodoreN;Yanagi,Hidenori;Yamamura,Takehira;Takahashi,Toku
上皮细胞的肠嗜铬细胞（EC）将5-HT释放到管腔以及基底外侧缘。然而，释放到管腔中的5-HT的生理作用知之甚少。采用高效液相色谱法测定大鼠结肠粘膜、结肠腔和粪便中5-HT的浓度。为了研究腔内5-HT是否加速结肠传输，将5-HT和51 Cr注入近端结肠腔内，并测量结肠传输。为了研究5-HT是否释放到管腔中，我们使用离体血管和管腔灌注大鼠近端结肠的anex vivomodel。为了研究管腔内5-HT是否参与调节应激诱导的结肠运动，在应激负荷下记录远端结肠运动，并在远端结肠管腔内给予5-HT 3受体拮抗剂（昂丹司琼，10− 6 M，0.5 ml）。近端结肠组织中5-HT含量（15.2 ± 4.3 ng/mg湿组织）显著高于远端结肠（3.3 ± 0.7 ng/mg湿组织），而近端结肠和远端结肠的粪便中5-HT含量和管腔中5-HT浓度几乎相同。腔内注射5-HT（10−6-10− 5 M）可显著加速结肠运输。10 cmH_2O升高管腔内压可显著增加5-HT的管腔浓度，但不增加血管内5-HT的浓度。应激诱导的刺激远端结肠运动显着衰减的恩丹西酮的管腔管理。提示EC细胞释放的5-HT在调节大鼠结肠运动中起重要作用。
Enterochromaffin (EC) cells of the epithelial cells release 5-HT into the lumen, as well as basolateral border. However, the physiological role of released 5-HT into the lumen is poorly understood. Concentrations of 5-HT in the colonic mucosa, colonic lumen, and feces were measured by HPLC in rats. To investigate whether intraluminal 5-HT accelerates colonic transit, 5-HT and51Cr were administered into the lumen of the proximal colon, and colonic transit was measured. To investigate whether 5-HT is released into the lumen, we used anex vivomodel of isolated vascularly and luminally perfused rat proximal colon. To investigate whether luminal 5-HT is involved in regulating stress-induced colonic motility, the distal colonic motility was recorded under the stress loading, and a 5-HT3receptor antagonist (ondansetron, 10−6M, 0.5 ml) was administered intraluminally of the distal colon. Tissue content of 5-HT in the proximal colon (15.2 ± 4.3 ng/mg wet tissue) was significantly higher than that in the distal colon (3.3 ± 0.7 ng/mg wet tissue), while fecal content and luminal concentration of 5-HT was almost the same between the proximal and distal colon. Luminal administration of 5-HT (10−6–10−5M) significantly accelerated colonic transit. Elevation of intraluminal pressure by 10 cmH2O significantly increased the luminal concentration of 5-HT but not the vascular concentration of 5-HT. Stress-induced stimulation of the distal colonic motility was significantly attenuated by the luminal administration of ondansetron. These results suggest that luminally released 5-HT from EC cells plays an important role in regulating colonic motility in rats.