新生鼠窒息后肾组织中钙离子的变化及意义

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45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2 h组(10只)，窒息后复氧24 h组(11只)，窒息后复氧48 h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2 h开始肾组织中Ca2+含量［(1.75±0.39) mmol/g］及左肾系数［(7.64±0.33) g/kg］、肾小管损伤评分(28.80±7.16)均较对照组［(1.44±0.46) mmol/g、(4.88±0.90) g/kg、5.46±1.76］显著升高，P<0.05。且肾损伤指标在24 h达到高峰。同时，肾组织中Ca2+含量与左肾系数在窒息后复氧2 h，24 h和48 h均呈显著正相关关系(r分别为 0.61，0.69 和 0.63，均P<0.05)；肾组织中Ca2+含量与肾小管评分在窒息后复氧2 h，24 h和48 h也呈显著正相关关系(r分别为 0.57，0.58 和 0.75，均P<0.05)。结论：钙离子参与了窒息后肾损伤的发生。

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

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.