新生鼠窒息后肾组织中钙离子的变化及意义

Changes and Significance of Ionic Calcium in Renal Tissues of Asphyxiated Neonatal Rats

目的 探讨新生鼠窒息后肾组织中钙离子的变化及意义。方法 将 4 5只 7～ 10日龄Wistar大白鼠随机分为 4组 :对照组 (13只 ) ,窒息后复氧 2h组 (10只 ) ,窒息后复氧 2 4h组 (11只 ) ,窒息后复氧 4 8h组 (11只 )。制成常压窒息模型。在上述各时间点取左肾称重求出左肾系数 (LRC) ,并测定出肾组织中Ca2 + 含量 ,同时在光镜下对肾小管损伤程度进行评分。结果 窒息后复氧 2h开始肾组织中Ca2 + 含量 [(1.75± 0 .39)mmol/g]及左肾系数 [(7.6 4± 0 .33)g/kg]、肾小管损伤评分 (2 8.80± 7.16 )均较对照组 [(1.4 4± 0 .4 6 )mmol/g、(4.88± 0 .90 )g/kg、5 .4 6± 1.76 ]显著升高 ,P <0 .0 5。且肾损伤指标在 2 4h达到高峰。同时 ,肾组织中Ca2 + 含量与左肾系数在窒息后复氧 2h ,2 4h和 4 8h均呈显著正相关关系 (r分别为 0 .6 1,0 .6 9和 0 .6 3,均P <0 .0 5 ) ;肾组织中Ca2 + 含量与肾小管评分在窒息后复氧 2h ,2 4h和 4 8h也呈显著正相关关系 (r分别为 0 .5 7,0 .5 8和 0 .75 ,均P <0 .0 5 )。

Objective To study the change and significance of ionic calcium (Ca 2+ ) in renal tissues of the neonatal rat after asphyxia. Methods Forty five 7-10 day neonatal Wistar rats were randomly assigned into 4 groups: the non asphyxiated controls (n=13), 2 h post asphyxia (n=10), 24 h post asphyxia (n=11) and 48 h post asphyxia (n=11). The animal model of the three experiment group was established by normobaric asphyxia. The left renal coefficient (LRC) was calculated; the content of Ca 2+ in the renal tissue was detected; and the scores of tubular injuries were evaluated under the light microscope at 2, 24 and 48 h after asphyxia. Results The LRC [( 7.64 ± 0.33 ) g/kg], the scores of tubular injuries ( 28.80 ± 7.16 ) and the content of Ca 2+ [( 1.75 ± 0.39 ) mmol/g] in the renal tissue obviously increased from 2 h of post asphyxia compared with the controls [( 4.88 ± 0.90 ) g/kg; ( 5.46 ± 1.76 ); ( 1.44 ± 0.46 ) mmol/g] (P< 0.05 ); and the scores of tubular injuries and the LRC reached to the peak at 24 h of post asphyxia. The content of Ca 2+ in the renal tissue was positively correlated with the LRC at 2, 24 and 48 h of post asphyxia (r= 0.61 , 0.69 , 0.63 , respectively; all P< 0.05 ). It was also positively correlated with the scores of tubular injuries at 2, 24 and 48 h of post asphyxia (r= 0.57 , 0.58 , 0.75 , respectively; all P< 0.05 ). Conclusions Ca 2+ may play a role in the development of renal injuries following asphyxia.