Spiegler M A, Oppenheimer S B
Department of Biology, California State University, Northridge 91330-8303, USA.
Cryobiology. 1995 Apr;32(2):168-74. doi: 10.1006/cryo.1995.1015.
The sea urchin is the material of choice for studying many early developmental events. Methods to extend the viability of sea urchin gametes have not received much attention, but it is well known that the eggs are easily damaged by freezing. This study was designed to extend the viability of Lytechinus pictus eggs and sperm without freezing. Gamete viability measurements were based on relative numbers of fertilized vs unfertilized eggs, percentage fertilization, and on observations of embryonic development. Results indicate that gametes can be stored longer and at lower temperatures than previously described. Sperm were consistently kept viable for at least 12 days with little decrease in viability when stored in glass test tubes or plastic petri dishes and submerged in ice inside a refrigerator at 0 +/- 1 degree C. In one experiment, sperm stored in glass test tubes on ice remained viable up to 20 days after extraction. Eggs were maintained from 1 to 7 days, rather than the 1 day or so previously reported, when stored in glass test tubes submerged in ice in a refrigerator at 0 +/- 1 degree C. Results of egg and sperm experiments varied at different times in the season. Such variations may be caused by seasonal cytoplasmic changes, population differences, or the time mature individuals were maintained unfed in aquaria prior to use. Results from this study should be useful for a variety of research, mariculture, and teaching applications in which sea urchin supplies are limited or when the same gamete population is required for subsequent experiments.
海胆是研究许多早期发育事件的首选材料。延长海胆配子活力的方法尚未受到太多关注，但众所周知，卵子很容易因冷冻而受损。本研究旨在不进行冷冻的情况下延长花斑丽海胆卵子和精子的活力。配子活力的测量基于受精卵子与未受精卵子的相对数量、受精百分比以及对胚胎发育的观察。结果表明，配子能够在比先前描述的更低温度下储存更长时间。当精子储存在玻璃试管或塑料培养皿中并浸没于0±1摄氏度的冰箱冰中时，其活力能持续保持至少12天，且活力几乎没有下降。在一项实验中，从冰上玻璃试管中取出的精子在提取后长达20天仍保持活力。当卵子储存在浸没于0±1摄氏度冰箱冰中的玻璃试管中时，可维持1至7天，而非先前报道的约1天。卵子和精子实验的结果在季节中的不同时间有所变化。这种变化可能是由季节性的细胞质变化、种群差异或成熟个体在使用前在水族箱中未喂食的时间长短所致。本研究结果对于海胆供应有限或后续实验需要相同配子群体的各种研究、海水养殖和教学应用应该是有用的。
