中文摘要：

以戈斯纳（Gosner 1960）分期表为标准,以花背蟾蜍（Pseudepidalea raddei）蝌蚪为研究对象,在46期蝌蚪小腿部位注射20μL不同浓度（1、2.5和5 mg·mL^-1）的植物血凝素（phytohemagglutinin-P,PHA-P）溶液,对侧同部位注射等量的生理盐水溶液,测定了注射前（0 h）及注射后3、6、9和12 h被注射部位组织厚度的变化情况,确定了蝌蚪对PHA-P反应的最适浓度;在最适浓度条件下,比较了37、42、44和46期蝌蚪对PHA-P的反应强度和持续时间。结果表明：46期蝌蚪对3种不同浓度的PHA-P溶液的反应无显著性差异,但反应峰值有先后,2.5 mg·mL^-1为最适注射浓度;42期蝌蚪在注射后3 h达反应峰值,而37、44和46期分别在注射后3-6、3-9及3-12 h出现反应峰值;37期蝌蚪对PHA-P的反应峰值高于46期,但与42和44期的蝌蚪无显著性差异;花背蟾蜍蝌蚪对PHA-P的反应模式随不同发育阶段而变化,42期为反应迅速、持续时间短的单峰值,其他水生阶段反应峰值有后延现象,且在登陆后反应峰值强度下降、持续时间延长,这可能与陆地多变的环境条件有关。

英文摘要：

Different developmental stages of tadpoles of Mongolian toads, Pseudepidalea raddei were identified by Gosner staging tables （Gosner, 1960）. 20 μL solution of three concentrations of phytohemagglutinin-P （PHA-P） （1, 2.5 and 5 mg·mL^-1） or equivalent salt was injected in one side or opposite one of lower legs of Gosner 46 tadpoles. The tissue thickness of injected sites was measured prior to injection （0 h）, and 3, 6, 9, and 12 h after injection, and an optimal PHA-P concentration was selected. Under the condition of optimal PHAP concentration, the intensity and latency of PHAP response were compared among Gosner 37, 42, 44 and 46 stages of tadpoles. The results showed that Gosner 46 tadpoles did not show significant differences after injection of the three levels of PHA-P, but the peak of PHA-P response appeared at earlier or later time, and 2.5 mg·mL^-1 was considered as the optimal injection dose. The PHA-P response of Gosner 42 tadpoles peaked at 3 h after the injection. The PHA-P response of Gosner 37, 44 and 46 tadpoles peaked at 3-6, 3-9, and 3-12 h after the injection, respectively. The maximal PHA-P response of Gosner 37 tadpoles was higher than that of Gosner 46 tadpoles, but there were no significant differences among Gosner 37, 42 and 44 tadpoles. The patterns of PHA-P response changed with different developmental stages of tadpoles in Mongolian toads. The single peak of PHA-P response was rapid and short in Gosner 42 tadpoles. The peak was delayed in the other aquatic developmental stages, and the intensity of the peak of the PHA-P response declined with prolonged duration in terrestrial tadpoles, which may be related to various environmental conditions on land.