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.