The influence of storage method on the transparency of pig crystalline lens

ABSTRACT Purpose: The porcine eye is frequently used as a research model. This paper analyzes the effect of different storage methods on the transparency of pig crystalline lens. Methods: A spectral transmission curve (from 220 to 780 nm) for the crystalline lens was determined experimentally after storage in different conditions: saline solution, formalin, castor oil, and freezing at -80°C. The total transmission in the visible spectrum, which was used as an index of transparency, was calculated from these curves. For comparative purposes, fresh lenses were evaluated and used as controls. Results: Storing the porcine crystalline lens in saline solution or castor oil resulted in a transparency loss of approximately 10% after 24 h and storage in formalin resulted in a loss of nearly 30%. Storage by freezing at -80°C for 4 weeks maintained the transparency of the crystalline lens; the spectral transmission measured immediately after defrosting at room temperature coincided exactly with that of the freshly extracted lens. Conclusions: The transparency of porcine crystalline lens is affected by the storage method. The visible spectrum is the most affected, evidenced by the effect on the transparency and consequently the amount of light transmitted. The results show that freezing at -80°C maintains the transpa rency of the crystalline lens for at least 4 weeks.

摘要 研究目的：猪眼常被用作科研模型。本文分析了不同保存方式对猪晶状体（porcine crystalline lens）透明度的影响。研究方法：分别将猪晶状体置于生理盐水（saline solution）、福尔马林（formalin）、蓖麻油（castor oil）中保存，以及采用-80℃冷冻保存，通过实验测定其光谱透射曲线（spectral transmission curve，波长范围220~780 nm）。以此计算可见光光谱（visible spectrum）内的总透射率，以此作为透明度的评价指标。为便于对比，同时设置新鲜晶状体作为对照样本并开展检测。研究结果：经24小时保存后，生理盐水或蓖麻油保存的猪晶状体透明度下降约10%，福尔马林保存者透明度下降近30%。采用-80℃冷冻保存4周的猪晶状体，其透明度得以维持；室温解冻后即刻测得的光谱透射曲线，与新鲜离体晶状体完全一致。研究结论：猪晶状体的透明度受保存方式影响显著，其中可见光光谱受影响最为明显，具体体现为透明度及透射光量的变化。本研究结果表明，-80℃冷冻保存可至少维持猪晶状体的透明度达4周。