Kim Hyun Chul, Lee Chi Hoon, Hur Sung Pyu, Kim Byeong Hoon, Park Jun Young, Lee Young Don
Genetics & Breeding Research Center, National Fisheries Research & Development Institute, Geoje 656-842, Korea.
Marine Science Institute, Jeju National University, Jeju 695-965, Korea.
Dev Reprod. 2015 Mar;19(1):11-7. doi: 10.12717/devrep.2015.19.1.011.
This study investigated possible involvement of photoperiodic regulation in reproductive endocrine system of female olive flounder. To investigate the influence on brain-pituitary axis in endocrine system by regulating photoperiod, compared expression level of Kisspeptin and sbGnRH mRNA in brain and FSH-β, LH-β and GH mRNA in pituitary before and after spawning. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from Aug. 2013 to Jun. 2014. Continuous long photoperiod treatment from Aug. (post-spawning phase) was inhibited gonadal development of female olive flounder. In natural photoperiod group, the Kiss2 expression level a significant declined in Mar. (spawning period). And also, FSH-β, LH-β and GH mRNA expression levels were increasing at this period. However, in long photoperiod group, hypothalamic Kiss2, FSH-β, LH-β and GH mRNA expression levels did not show any significant fluctuation. These results suggest that expression of hypothalamic Kiss2, GtH and GH in the pituitary would change in response to photoperiod and their possible involvement of photoperiodic regulation in reproductive endocrine system of the BPG axis.
本研究调查了光周期调节在雌性牙鲆生殖内分泌系统中可能发挥的作用。为了通过调节光周期来研究其对内分泌系统中脑垂体轴的影响，比较了产卵前后脑中Kisspeptin和sbGnRH mRNA以及垂体中FSH-β、LH-β和GH mRNA的表达水平。光周期处理为2013年8月至2014年6月的自然光周期和长光周期（15小时光照：9小时黑暗）条件。从8月（产卵后期）开始的连续长光周期处理抑制了雌性牙鲆的性腺发育。在自然光周期组中，3月（产卵期）Kiss2表达水平显著下降。并且在此期间FSH-β、LH-β和GH mRNA表达水平升高。然而，在长光周期组中，下丘脑Kiss2、FSH-β、LH-β和GH mRNA表达水平未显示出任何显著波动。这些结果表明，下丘脑Kiss2、垂体中的促性腺激素和GH的表达会因光周期而变化，并且它们可能参与了脑垂体性腺轴生殖内分泌系统的光周期调节。
