Evaluation of Renal Microhemodynamics Heterogeneity in Different Strains and Sexes of Mice

Addressing the existing gaps in our understanding of renal microhemodynamics across diverse mouse strains and sexes, this study conducts an in-depth investigation into the variations in renal function and related biological oscillators. Laser Doppler and wavelet analysis were applied to BALB/c, C57BL/6, and KM mice, widely used strains in studies of renal microcirculatory dysfunction and related diseases. We examined serum creatinine, urea, uric acid, glucose, and cystatin C for dissimilarities across strains and sexes. Notable disparities in glucose, urea, cystatin C, and creatinine levels were detected between the sexes within C57BL/6 and KM strains, along with strain-specific differences among both females and males. Relationships between renal function and microhemodynamics were uncovered through Mantel and Pearson correlation analysis, notably with creatinine and uric acid in female BALB/c mice, and cystatin C in male C57BL/6 mice. Histological evaluations revealed higher microvascular density in females compared to males across all strains, alongside variations in CD31 expression between sexes and strains. Despite these differences, the expression of estrogen receptor α and β in renal microvasculature did not significantly differ across sexes, except for estrogen receptor β expression variation between C57BL/6 and KM females. These findings underscore the substantial influence of mouse strain and gender on renal microcirculatory function indicators.

针对当前学界对不同品系及性别小鼠肾脏微血流动力学认知存在的空白，本研究针对肾脏功能及相关生物振荡器（biological oscillators）的差异展开深入探究。本研究采用激光多普勒（Laser Doppler）与小波分析（wavelet analysis）技术，对肾脏微循环障碍及相关疾病研究中广泛使用的BALB/c、C57BL/6与KM三种小鼠品系开展实验。我们检测了血清肌酐、尿素、尿酸、葡萄糖及半胱氨酸蛋白酶抑制剂C（cystatin C）的水平，以分析不同品系与性别间的差异。在C57BL/6与KM品系中，雌雄小鼠间的葡萄糖、尿素、半胱氨酸蛋白酶抑制剂C及肌酐水平存在显著差异；同时雌雄小鼠内部亦存在品系特异性差异。通过曼特尔（Mantel）与皮尔逊（Pearson）相关分析，本研究揭示了肾脏功能与微血流动力学之间的关联：雌性BALB/c小鼠中该关联主要体现在肌酐与尿酸水平，而雄性C57BL/6小鼠中则体现为半胱氨酸蛋白酶抑制剂C水平。组织学评估结果显示，所有品系的雌性小鼠微血管密度均高于雄性小鼠，且不同性别与品系间的CD31表达亦存在差异。尽管存在上述差异，肾脏微血管中雌激素受体α（estrogen receptor α）与β（estrogen receptor β）的表达在不同性别间并无显著差异，仅C57BL/6与KM品系雌性小鼠的雌激素受体β表达存在差异。本研究结果证实，小鼠品系与性别对肾脏微循环功能指标存在显著影响。