17α-P和PGE_2暴露对中华乌塘鳢排卵以及嗅觉系统孕酮和PGE_2受体表达的影响

Effects of 17α-P and PGE_2 on ovulation and expression of PR and EPs immunoreactivity in the olfactory system of Bostrichthys sinensis

将性成熟中华乌塘鳢(Bostrichthys sinensis)分别暴露于性信息素17α-P和PGE2 24 h和48 h后,检测其排卵率,并应用免疫细胞化学(SABC)法检测嗅觉系统上17α-P受体(PR)和PGE2受体(EPs)免疫阳性细胞数量的变化。结果发现暴露后雌鱼排卵率升高,且暴露48 h后的排卵率高于暴露24 h后的排卵率;嗅觉系统PR和EPs免疫阳性细胞数量增加。雌鱼排卵率的升高与PR和EPs免疫阳性细胞数量的增加具有一致性。研究结果提示,环境中的17α-P和PGE2有可能通过中华乌塘鳢嗅觉系统受体PR和EPs的介导,影响其生殖状态。

Our prior research suggests that 17a-P and PGE2 may act as putative sex pheromones in Chinese black sleeper （Bostrichthys sinensis）, and that the pheromones are likely detected through the olfactory system by 17a-P receptors （PRs） and PGE2 receptors （EPs）. During the spawning season, after mature B. sinensis were exposed to 17a-P or PGE2 for 24 h and 48 h, we measured the ovulation rates and quantified the immunoreactivities of PR and EPs in the olfactory system using SABC immunoeytochemistry. The ovulation rates of females increased after exposure to 17a-P or PGE2 for 24 h and 48 h. Furthermore, the rate was the higher after 48 h exposure than after 24 h exposure. The increase in numbers of PR and EPs immunoreactive cells was the highest in the olfactory epi- thelium, followed by the olfactory bulb, and the olfactory nerve was the lowest exposed to 17a-P or PGE2. The increases in the number of PR and EPs immunoreactive cells were consistent with the increases in ovulation rate. Our results suggest that water-borne 17a-P and PGE2 affect the reproductive status of B. sinensis via the PRs and EPs in the olfactory system. We also discuss the potential mechanisms of sex pheromone reception and transduc- tion in the B. sinensis olfactory system.