Application of the isolated perfused rat kidney model to assess gender effects on drug excretion

An Isolated Perfused Rat Kidney Model for the Evaluation of the Effect of Glucose on Renal Tubular Epithelial Morphology

An isolated perfused kidney model was used to evaluate the effect of hyperglycemia on renal tubular epithelial cell morphology. Ten Sprague-Dawley rat kidneys were perfused with Krebs-Henseleit buffer containing 70 mmol/L of glucose (five for 1 h and five for 2 h). Two control groups consisted of 10 kidneys perfused with Krebs-Henseleit buffer without hyperglycemia (five for 1 h and five for 2 h), and 10 nonperfused contralateral kidneys placed in the same environment for the same duration. The hyperglycemia group had significantly increased renal tubular vacuolization (p < 0.001) compared to both control groups at 1 and 2 h. The isolated perfused kidney model recapitulates the renal tubular vacuolization phenotype found in hyperglycemia and may be a potential tool for the investigation into causal factors in renal histology. The full pattern of the Armanni-Ebstein phenomenon was not, however, reproduced, suggesting that this change requires more time or involves more complex factors.

Gender differences in kidney function

Sex hormones influence the development of female (F) and male (M) specific traits and primarily affect the structure and function of gender-specific organs. Recent studies also indicated their important roles in regulating structure and/or function of nearly every tissue and organ in the mammalian body, including the kidneys, causing gender differences in a variety of characteristics. Clinical observations in humans and studies in experimental animals in vivo and in models in vitro have shown that renal structure and functions under various physiological, pharmacological, and toxicological conditions are different in M and F, and that these differences may be related to the sex-hormone-regulated expression and action of transporters in the apical and basolateral membrane of nephron epithelial cells. In this review we have collected published data on gender differences in renal functions, transporters and other related parameters, and present our own microarray data on messenger RNA expression for various transporters in the kidney cortex of M and F rats. With these data we would like to emphasize the importance of sex hormones in regulation of a variety of renal transport functions and to initiate further studies of gender-related differences in kidney structure and functions, which would enable us to better understand occurrence and development of various renal diseases, pharmacotherapy, and drug-induced nephrotoxicity in humans and animals.