Tilden A R, Rasmussen P, Awantang R M, Furlan S, Goldstein J, Palsgrove M, Sauer A
Biology Department, Macalester College, St. Paul, Minnesota 55105, USA.
J Pineal Res. 1997 Oct;23(3):142-7. doi: 10.1111/j.1600-079x.1997.tb00347.x.
Melatonin was measured over 24 hr in the eyestalks of Uca pugilator by means of radioimmunoassay; crabs were acclimatized either to a LD 12:12 photoperiod or constant darkness. A significant peak occurred at 13.00 hr in the LD 12:12 crabs. A photophase peak in melatonin has only been reported in one other species, also a crustacean. In constant darkness, two melatonin peaks occurred, one at 16.00 hr and the other 12 hr later; these results suggest that the melatonin cycle is a true circadian rhythm. HPLC with ultraviolet-visible detection was used to confirm the identity of melatonin immunoactivity. The influence of melatonin on regeneration of the walking legs was also examined: eyestalks were either removed or left intact, and limb bud length was measured every other day for at least 17 days in control and melatonin-treated crabs (60 microg ml(-1) seawater). Melatonin significantly increased the rate of limb regeneration in both eyestalk-intact and eyestalk-removed groups; this is contrary to results of regeneration studies in other phyla, in which similar melatonin concentrations inhibited regeneration.
通过放射免疫分析法在24小时内测定了战斗招潮蟹眼柄中的褪黑素；将螃蟹分别适应12:12的光照周期或持续黑暗环境。在12:12光照周期的螃蟹中，褪黑素在13:00时出现显著峰值。褪黑素的光期峰值仅在另一个物种（也是一种甲壳类动物）中有过报道。在持续黑暗环境中，出现了两个褪黑素峰值，一个在16:00时，另一个在12小时后；这些结果表明褪黑素周期是一种真正的昼夜节律。使用带有紫外可见检测的高效液相色谱法来确认褪黑素免疫活性的特性。还研究了褪黑素对步足再生的影响：切除或保留眼柄，在对照和褪黑素处理的螃蟹（60微克/毫升海水）中每隔一天测量一次肢芽长度，至少持续17天。褪黑素显著提高了保留眼柄和切除眼柄组的肢体再生速率；这与其他门的再生研究结果相反，在其他研究中，类似浓度的褪黑素会抑制再生。
