Pinto P I S, Estêvão M D, Redruello B, Socorro S M, Canário A V M, Power D M
Centro de Ciências do Mar, CIMAR-Laboratório Associado, University of Algarve, Campus de Gambelas, Faro, Portugal.
Gen Comp Endocrinol. 2009 Jan 1;160(1):19-29. doi: 10.1016/j.ygcen.2008.10.011. Epub 2008 Oct 17.
Calcium mobilization from internal stores, such as scales, induced by 17beta-estradiol during sexual maturation in salmonids is well documented. This calcium mobilization from scales is proposed to be mediated by the estrogen receptor (ER). However, the ER subtypes involved and signaling mechanisms responsible for this effect remain to be fully characterized. In the present study, we have localized ERalpha, ERbetaa and ERbetab proteins in juvenile and adult sea bream (Sparus auratus) and Mozambique tilapia (Oreochromis mossambicus) scales by immunohistochemistry with sea bream ER subtype specific antibodies. The three ERs were detected in isolated or small groups of round cells, in the basal layer of the scales of both juvenile and adult fish and the localization and signal intensity varied with the species and age of the animals. The ERs may be co-localized in cells of the scale posterior region that expressed tartrate-resistant acid phosphatase (TRAP), a marker for osteoclasts. These results suggest that the calcium mobilizing action of 17beta-estradiol on fish scales is via its direct action on ERs localized in osteoclasts.
在鲑科鱼类性成熟过程中，17β-雌二醇诱导从诸如鳞片等内部储存库中动员钙的现象已有充分记录。这种从鳞片中动员钙的过程被认为是由雌激素受体（ER）介导的。然而，所涉及的ER亚型以及负责此效应的信号传导机制仍有待充分表征。在本研究中，我们使用海鲷ER亚型特异性抗体通过免疫组织化学方法，在幼年和成年海鲷（Sparus auratus）以及莫桑比克罗非鱼（Oreochromis mossambicus）的鳞片中定位了ERα、ERβa和ERβb蛋白。在幼年和成年鱼鳞片的基底层中，在孤立的或小群的圆形细胞中检测到了这三种ER，其定位和信号强度随动物的物种和年龄而变化。ER可能共定位于鳞片后部区域表达抗酒石酸酸性磷酸酶（TRAP，一种破骨细胞标记物）的细胞中。这些结果表明，17β-雌二醇对鱼鳞的钙动员作用是通过其对定位于破骨细胞中的ER的直接作用实现的。
