黑龙江林蛙胃肠道5-羟色胺细胞的胚后发生

5-Hydroxytryptamine Cells in Gastrointestinal Tract during the Postembryonic Development of Siberian Wood Frog(Rana amurensis)

采用亲和素-生物素复合物(ABC)免疫组织化学法,对黑龙江林蛙(Rana amurensis)胚后发育各时期胃肠道中5-羟色胺(5-HT)细胞的发生过程进行了研究。结果显示,黑龙江林蛙胃中的5-羟色胺阳性细胞最早在第38期被检测到,小肠和大肠最早出现在第41期。从41期开始,5-羟色胺细胞分布于胃、小肠和大肠中,在同一发育时期中,胃部分布密度最大。同一部位在不同发育时期5-羟色胺细胞的分布密度不同,其中胃内5-羟色胺细胞在38期和43期分布最多,分布密度分别为1.8±0.62和1.8±0.89,45期分布数量最少,分布密度为1.1±0.31;小肠中5-羟色胺细胞在41期和43期分布最多,分布密度均为1.2±0.41,在44期和45期分布最少,分布密度分别为0.7±0.49和0.7±0.47;大肠中5-羟色胺细胞在第42期分布最多,分布密度为1.2±0.41,在44期分布最少,分布密度为0.7±0.47。5-羟色胺细胞最早分布在上皮细胞之间,随着胃肠道发育的日渐完善,在上皮基部或腺泡上皮之间也有分布。细胞形态变化不明显,有圆形、椭圆形、锥体形、长梭形和三角形。推测5-羟色胺阳性细胞的出现时间、形态以及分布型是与黑龙江林蛙的个体生长发育需要、胃肠道各段的功能以及食性转变相适应的。

An immunohistochemical（avidin-biotin complex method, ABC） method was employed to study the 5-hydroxytryptamine（5-HT） cells in the gastrointestinal tract during postembryonic development of Siberian wood frog（Rana amurensis）. The 5-HT positive cells were firstly found in the stomach at the 38 th stage and were observed in the small intestine and the large intestine at the 41 st stage. The 5-HT cells distributed throughout the stomach, small intestine and large intestine after the 41 st stage. Of the identical growth stage, the density of 5-HT cells were the highest in the stomach. The distribution densities of the same position in different development periods of 5-HT cells were different. The stomach 5-HT cells were most widely distributed at stages 38 and 43, respectively（1.8 ± 0.62 and 1.8 ± 0.89）; the distribution density was the least at stage 45（1.1 ± 0.31）. The distribution density of 5-HT cells in small intestine was the highest at stages 41 and 43（1.2 ± 0.41）. The distribution density was the least at stages 44 and 45, respectively（0.7 ± 0.49 and 0.7 ± 0.47）. The 5-HT cells were most widely distributed in large intestine at the stage 42（1.2 ± 0.41）, while the density was. The least at stage 44（0.7 ± 0.47）. The 5-HT cells first appeared in intercellular space of epithelium. With the development of the gastrointestinal tract, the 5-HT cells also distributed at the basal part of epithelium or the between acinar epithelial cells. The morphology changes of cells were not obvious, mainly in round, ellipse, cone-shaped, shuttle-shaped, and triangle. We conclude that the appearance time, shape and distribution of 5-HT cells correspond to individual growth needs, gastrointestinal function, and diet shifts of Rana amurensis.