Parmeggiani A, Govoni N, Zannoni A, Di Biase A, Sirri R, Forni M, Mandelli M, Mordenti O
Department of Veterinary Medical Sciences, DIMEVET, Bologna University, Bologna, Italy.
Department of Veterinary Medical Sciences, DIMEVET, Bologna University, Bologna, Italy.
Theriogenology. 2015 Mar 1;83(4):478-84. doi: 10.1016/j.theriogenology.2014.10.008. Epub 2014 Oct 15.
The aim of this work was to determine the effects of dark and light conditions on the E2, testosterone and thyroid hormones levels and on the gene expression levels (vitellogenin 1, vitellogenin 2, and estradiol receptor one) in European eels (Anguilla anguilla) during ovarian development induced by increasing doses of carp pituitary extracts (CPEs). The subjects were divided into 2 groups: 14-hour light:10-hour dark (Light Group) and 24-hour darkness (Dark Group). All the eels received intramuscular injections with CPE at a dosage of 10 mg/kg body weight (BW) once a week for the first 3 weeks, 20 mg/kg BW fourth-sixth week, 30 mg/kg BW seventh-ninth week, and 40 mg/kg up to the end of the experiment (13th week). Vitellogenin and estradiol receptor expression levels did not show significant differences between the two housing conditions whereas in both groups vitellogenin mRNA increased starting from first CPE injection. Testosterone and 17-beta estradiol plasma levels were significantly greater in the Dark Group compared with the Light Group starting from the ninth and the 13th week, respectively. These results suggest that darkness could be a useful variable for standardizing gonadal maturation in eels kept in captivity.
本研究的目的是确定在通过增加鲤鱼垂体提取物（CPE）剂量诱导欧洲鳗鲡（Anguilla anguilla）卵巢发育过程中，黑暗和光照条件对E2、睾酮和甲状腺激素水平以及基因表达水平（卵黄蛋白原1、卵黄蛋白原2和雌二醇受体1）的影响。实验对象分为两组：14小时光照：10小时黑暗（光照组）和24小时黑暗（黑暗组）。所有鳗鲡在实验的前三周每周接受一次剂量为10mg/kg体重（BW）的CPE肌肉注射，第四至六周为20mg/kg BW，第七至九周为30mg/kg BW，直至实验结束（第13周）为40mg/kg BW。两种饲养条件下，卵黄蛋白原和雌二醇受体的表达水平没有显著差异，而在两组中，从第一次注射CPE开始，卵黄蛋白原mRNA均增加。黑暗组的睾酮和17-β雌二醇血浆水平分别从第九周和第十三周开始显著高于光照组。这些结果表明，黑暗可能是使圈养鳗鲡性腺成熟标准化的一个有用变量。
