家兔玻璃体液间隔多次微量取样方法研究

A study on interval multiple micro-sampling of vitreous humor on rabbits

目的探讨间隔多次微量取样玻璃体液是否可用于死亡时间推断。方法99只家兔分为2大组(I)大组45只,再分为A、B、C、D、E五个小组(每组9只),右眼(实验眼)于死后间隔12h多次取样直至24h(A组)、48h(B组)、72h(C组)、96h(D组)和120h(E组);各小组左眼(对照眼)仅分别于死后24h、48h、72h、96h和120h取样一次。检测Ca2+、Cl-、K+、Na+和P含量,同一取样时间的双眼做配对t检验。(II)大组54只,再分为2小组F组9只,每隔12h双眼交替多次取样直至120h;G组45只,每隔12h一次取样10眼(动物左右眼均编号后随机抽取每次10眼),直至120h;检测Ca2+、K+和Na+,两组差值做t检验及PMI回归方程比较。结果E组K+有差异(P<0.05),其余A^E组双眼物质含量配对t检验均无差异(P>0.05)。F与G组物质含量差值t检验无差异(P>0.05);K+、Na+的PMI线性回归方程的斜率、截距无差异(P>0.05),Ca2+与PMI无相关性。结论控制间隔时间和取样次数,多次微量取样对死后玻璃体液元素含量的规律性变化无显著影响,可以替代传统方法进行死亡时间研究。

Objective To explore if the interval multiple micro-sampling of vitreous humor （VH） could be used for postmortem interval （PMI） estimation. Methods Ninety-nine rabbits were divided into two groups. The forty-five animals in group Ⅰ were subdivided into five sub-groups of nine in each group. Right eyes （experimental eyes） were multiple micro-sampled at intervals of 12h up to 24h postmortem in subgroup A, 48h in sub-group B, 72h in sub-group C, 96h in sub-group D and 120h in sub-group E respectively, while left eyes （contrast eyes） were micro-sampled only at 24h, 48h, 72h, 96h and 120h postmortem by which sub-group they were in. The contents of calcium, chlorine, potassium, sodium and phosphorus were detected and pair-matching t-tests between eyes with identical sampling time were carried out. Fifty-four rabbits of group Ⅱ were subdivided into two sub-groups, nine in sub-group F and forty-five in sub-group G. Rabbits in sub-group F were multiple micro-sampled alternatively between right and left eyes at intervals of 12h from 12h to 120h postmortem. As to sub-group G, forty-five rabbits with all eyes numbered then divided randomly 10 eyes in one batch micro-sampled every 12h also from 12h to 120h postmortem. The concentrations of calcium, potassium and sodium were detected, and difference t-tests and PMI linear regression equations of sub-group F and G were performed for comparison. Results Only the potassium in subgroup E showed significant difference （P =0.025）, all others showed no significant difference in sub-group A-E （P 〉0.05）. The different t-test between sub-group F and G presented no significant difference （P 〉0.05 ）. The comparison of PMI linear regression equations of potassium and sodium between sub-group F and G also showed no significant difference （ P 〉 0. 05 ）, and calcium in both subgroups had no correlation to PMI.Conclusion With proper control of interval extent and sampling times, multiple micro-sampling does not affect the regularity of element contents in vitreous humor, and can be used for PMI investigation.