School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA.
Comp Biochem Physiol B Biochem Mol Biol. 2012 Nov-Dec;163(3-4):285-91. doi: 10.1016/j.cbpb.2012.06.005. Epub 2012 Jul 5.
Carotenoid pigments can be allocated to different parts of the body to serve specific functions. In contrast to other body tissues, studies of carotenoid resources in the testes of animals are relatively scarce. We used high-performance liquid chromatography to determine the types and concentrations of carotenoids in the testes of house finches (Carpodacus mexicanus). Additionally, we examined the relationships between testes carotenoid concentrations and carotenoid pools in other body tissues, as well as body mass, testes mass and plumage coloration. We detected low concentrations of several carotenoids - lutein (the predominant carotenoid), zeaxanthin, anhydrolutein, β-cryptoxanthin, β-carotene and an unknown carotene - in the testes of wild house finches. We also found that testes lutein levels were significantly and positively associated with circulating lutein levels, while the concentration of zeaxanthin in testes was positively associated with zeaxanthin levels in liver, though in this instance the relationship was much weaker and only marginally significant. Furthermore, lutein levels in testes were significantly negatively associated with testes mass. Finally, plumage coloration was not associated with either the concentration of carotenoids in the testes or relative testes mass. These results suggest that testes carotenoids are reflective of the pool of circulating carotenoids in house finches, and that plumage coloration is unlikely to signal either the carotenoid content of testes tissue or a male's capacity for sperm production.
类胡萝卜素色素可以分配到身体的不同部位，以发挥特定的功能。与其他身体组织不同，对动物睾丸中类胡萝卜素资源的研究相对较少。我们使用高效液相色谱法测定了家雀（Carpodacus mexicanus）睾丸中的类胡萝卜素类型和浓度。此外，我们还研究了睾丸类胡萝卜素浓度与其他身体组织中的类胡萝卜素库、体重、睾丸质量和羽毛颜色之间的关系。我们在野生家雀的睾丸中检测到了几种低浓度的类胡萝卜素——叶黄素（主要类胡萝卜素）、玉米黄质、脱水叶黄素、β-隐黄质、β-胡萝卜素和一种未知的类胡萝卜素。我们还发现，睾丸叶黄素水平与循环叶黄素水平呈显著正相关，而睾丸玉米黄质浓度与肝脏玉米黄质水平呈正相关，尽管这种关系较弱，且仅略有统计学意义。此外，睾丸叶黄素水平与睾丸质量呈显著负相关。最后，羽毛颜色与睾丸中类胡萝卜素的浓度或相对睾丸质量均无相关性。这些结果表明，睾丸中的类胡萝卜素反映了家雀循环类胡萝卜素库中的情况，而羽毛颜色不太可能表明睾丸组织中的类胡萝卜素含量或雄性的精子生成能力。
