Xiao Kan, Huang Hongtao, Shi Xuetao, Shu Tingting, Cheng Xu, Du Hejun, Yang Jing
Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes, Yichang 443100, China.
Chinese Sturgeon Research Institute, China Three Gorges Corporation, Yichang 443100, China.
Animals (Basel). 2024 Jan 11;14(2):227. doi: 10.3390/ani14020227.
As an ancient and endangered species unique to the Yangtze River in China, the wild population of the Dabry's sturgeon has become scarce. Due to the long time till the first sexual maturity of Dabry's sturgeon, the population of artificially bred Dabry's sturgeon recovered slowly. As a member of the tachykinin family, TAC1 has been reported to have a variety of functions in mammals such as pain control, smooth muscle contraction and reproductive cycle regulation, but the function of Tac1 in fish has been rarely reported. In this study, we synthesized two gene products, Substance P (SP) and neurokinin A (NKA), and further verified the effect of two gene products on the secretion of related hormones in the pituitary of Dabry's Sturgeon by intraperitoneal injection and co-culture of primary cells. Expression studies revealed that the newly cloned were mainly distributed in the hypothalamus and pituitary tissue of the brain. In prepubertal Dabry's sturgeon, this study showed that the two gonadotropins' mRNA levels in pituitary tissue can be significantly increased by SP and NKA through intraperitoneal injection, and the LH protein level in serum was also increased. Further study showed that both NKA and SP could promote the two gonadotropins' mRNA expression in pituitary cells of Dabry's sturgeon. In addition, we explored the optimal dose and time of SP and NKA on pituitary cells is 24 h and over 10 nM. These results, as a whole, suggested that gene products play an important role in gonadotropin release and gonadal development in prepubertal Dabry's sturgeon.
达氏鲟作为中国长江特有的古老濒危物种，其野生种群已变得稀少。由于达氏鲟首次性成熟所需时间较长，人工养殖的达氏鲟种群恢复缓慢。作为速激肽家族的一员，据报道TAC1在哺乳动物中具有多种功能，如疼痛控制、平滑肌收缩和生殖周期调节，但Tac1在鱼类中的功能鲜有报道。在本研究中，我们合成了两种基因产物，即P物质（SP）和神经激肽A（NKA），并通过腹腔注射和原代细胞共培养进一步验证了这两种基因产物对达氏鲟垂体中相关激素分泌的影响。表达研究表明，新克隆的基因主要分布在脑的下丘脑和垂体组织中。在青春期前的达氏鲟中，本研究表明，通过腹腔注射，SP和NKA可显著提高垂体组织中两种促性腺激素的mRNA水平，血清中的LH蛋白水平也有所升高。进一步研究表明，NKA和SP均可促进达氏鲟垂体细胞中两种促性腺激素的mRNA表达。此外，我们还探究了SP和NKA作用于垂体细胞的最佳剂量和时间为24小时且浓度超过10 nM。总体而言，这些结果表明基因产物在青春期前达氏鲟的促性腺激素释放和性腺发育中发挥着重要作用。
