Tarrant A M, Atkinson S, Atkinson M J
Department of Oceanography, University of Hawaii at Manoa, Honolulu 96822, USA.
Comp Biochem Physiol A Mol Integr Physiol. 1999 Jan;122(1):85-92. doi: 10.1016/s1095-6433(98)10155-1.
Spawnings of scleractinian corals are affected by light, temperature, and other environmental cues, but no studies elucidate physiological mechanisms that regulate coral gametogenesis. We hypothesized that estrogens may act as bioregulators of coral reproduction. Estrone (E1) and estradiol-17 beta (E2) concentrations were measured in homogenates of tissue and skeleton from M. verrucosa. Tissue samples were collected monthly throughout the year, and more frequently in July and August around spawning. Steroids were extracted with diethyl ether, purified via celite chromatography and assayed with radioimmunoassay. Non-specific binding in coral tissue varied with sample weight and was elevated relative to standards. Monthly mean E1 ranged from 20-70 ng E1 g ash-free dry weight (AFDW)-1, with highest values in April. Smaller asynchronous peaks occurred in early July, prior to spawning. Monthly mean E2 ranged from 8-25 ng E2 g AFDW-1, with highest values in February and March. Peaks in E2 preceded peaks in E1, indicating metabolism of a pool of estrogen. E1 was positively correlated with protein concentration, which is consistent with a bioregulatory role of estrogens. Estrogen peaks in spring and prior to the July spawn corroborate our hypothesis that estrogens regulate coral gametogenesis and spawning.
石珊瑚的产卵受光照、温度和其他环境线索影响，但尚无研究阐明调节珊瑚配子发生的生理机制。我们推测雌激素可能作为珊瑚繁殖的生物调节剂。测定了疣状杯形珊瑚组织和骨骼匀浆中的雌酮（E1）和雌二醇-17β（E2）浓度。全年每月采集组织样本，在7月和8月产卵前后采集更为频繁。用乙醚提取类固醇，通过硅藻土色谱法纯化，并用放射免疫分析法测定。珊瑚组织中的非特异性结合随样本重量而变化，相对于标准品有所升高。每月平均E1范围为20 - 70 ng E1 g无灰干重（AFDW）-1，4月时最高。在7月初产卵前出现较小的异步峰值。每月平均E2范围为8 - 25 ng E2 g AFDW-1，2月和3月时最高。E2峰值先于E1峰值出现，表明存在雌激素池的代谢。E1与蛋白质浓度呈正相关，这与雌激素的生物调节作用一致。春季和7月产卵前的雌激素峰值证实了我们的假设，即雌激素调节珊瑚配子发生和产卵。
