Björnsson B T, Taranger G L, Hansen T, Stefansson S O, Haux C
Department of Zoophysiology, University of Göteborg, Sweden.
Gen Comp Endocrinol. 1994 Jan;93(1):70-81. doi: 10.1006/gcen.1994.1009.
The plasma profiles of growth hormone (GH) in adult male and female Atlantic salmon were determined in relation to manipulation of the photoperiod and to the development and timing of sexual maturation. Fish were exposed to natural light (NL) or NL + 24L:0D additional light over the netpens from January (ALJ) or March (ALM) to July. Thereafter, these groups were brought indoors, subdivided, and subjected to simulated natural photoperiod (SNP), continuous light (24L), or short day (8L). Assay of salmon GH by RIA in monthly plasma samples revealed that GH levels were generally < 1 ng ml-1 during January to June and were only slightly affected by additional light in January or March. ALJ-24L treatment, and to a lesser extent, ALM-24L treatment, was effective in preventing sexual maturation, and GH levels of immature fish continued to be < or = 1.5 ng ml-1. On the other hand, in sexually maturing fish, GH levels increased to 2-5 ng ml-1 months prior to ovulation. Short-day photoperiod (8L) from July advanced ovulation and spermiation, whereas continuous light from July delayed these processes. The timing of the increase of GH levels was shifted in a parallel manner, indicating a functional relationship between plasma GH levels and the process of sexual maturation.
测定了成年雄性和雌性大西洋鲑生长激素（GH）的血浆水平，以研究光周期调控、性成熟发育及时间安排之间的关系。从1月（1月开始增加光照，ALJ）或3月（3月开始增加光照，ALM）至7月，将鱼置于自然光（NL）下，或在网箱上方给予NL + 24小时光照。之后，将这些组带回室内，进行细分，并使其接受模拟自然光周期（SNP）、持续光照（24L）或短日照（8L）处理。通过放射免疫分析法（RIA）对每月血浆样本中的鲑鱼GH进行测定，结果显示，1月至6月期间GH水平通常<1 ng/ml，1月或3月增加光照对其影响甚微。ALJ - 24L处理以及在较小程度上的ALM - 24L处理可有效防止性成熟，未成熟鱼的GH水平持续≤1.5 ng/ml。另一方面，在性成熟的鱼中，排卵前几个月GH水平升至2 - 5 ng/ml。7月开始的短日照光周期（8L）可提前排卵和排精，而7月开始的持续光照则会延迟这些过程。GH水平升高的时间也相应发生了变化，这表明血浆GH水平与性成熟过程之间存在功能关系。
