甲醛缓释体类防腐剂对活体兔巩膜交联有效性的研究

目的：通过研究甲醛缓释体类防腐剂(FARs)对活体兔巩膜交联后的巩膜生物力学强度的改变来衡量其有效性。

方法：将健康新西兰白兔170只随机分为17组，其中15组为FARs药物组(羟甲基甘氨酸钠、重氮咪唑烷基脲、咪唑烷基脲、乙内酰脲、恶唑烷，每种药物根据给药浓度分为1/10最大允许浓度组、1/2最大允许浓度组、最大允许浓度组)，另设戊二醛(阳性对照)组、空白对照组，于右眼结膜下注射相应药物。60d后取右眼鼻上1：00位和颞下7：00位巩膜并制成巩膜条带，检测其厚度、弹性模量、蠕变率、极限应力、极限应变以衡量巩膜生物力学强度。

结果：羟甲基甘氨酸钠、重氮咪唑烷基脲、咪唑烷基脲、乙内酰脲、恶唑烷均可增强巩膜生物力学强度，且具有一定的药物浓度依赖性，其中羟甲基甘氨酸钠、重氮咪唑烷基脲、恶唑烷三种药物交联效果较强，在1/10最大允许浓度下效果明显。

结论：羟甲基甘氨酸钠、重氮咪唑烷基脲、恶唑烷具备较强的巩膜胶原交联效应，能够显著提高后巩膜生物力学强度，具备治疗病理性近视的潜能。

Study on the efficacy of formaldehyde sustained-release preservatives in scleral cross-linking of living rabbits

AIM: To evaluate the efficacy of formaldehyde release agents(FARs)on scleral cross-linking in living rabbits by measuring the changes in scleral biomechanical properties after the cross-linking.

METHODS: Totally 170 healthy New Zealand white rabbits were randomized into 17 groups, including 15 FARs groups(sodium hydroxymethylglycinate, diazolidinyl urea, imidazolidinyl urea, hydantoin and oxazolidine, each of them has three groups based on dosing concentration: 1/10 maximum allowable concentration group, 1/2 maximum allowable concentration group and maximum allowable concentration group), 1 glutaraldehyde(positive control)group and 1 blank control group. Subconjunctivally injected each FAR in the right eye. 60d after the injection, took the sclera at 1:00 and 7:00 sites of the right eye to make scleral strips. The scleral strip''s thickness, elastic modulus, creep rate, ultimate stress and ultimate strain were measured to calculate the scleral biomechanical strength.

RESULTS: Sodium hydroxymethylglycinate, diazolidinyl urea, imidazolidinyl urea, hydantoin and oxazolidine increased the scleral biomechanical strength in a concentration-dependent manner. In these drugs, sodium hydroxymethylglycinate, diazolidinyl urea and oxazolidine had strong cross-linking effects, with obvious effects at the 1/10 maximum allowable concentration.

CONCLUSION: Sodium hydroxymethylglycinate, diazoimidazolidinyl urea, and oxazolidine have strong effects on sclera collagen cross-linking, can significantly improve the biomechanical strength of posterior sclera and have the potential to treat pathological myopia.