Estimation of glomerular filtration rate in rabbits by a single-sample method using iodixanol

Area of Science:

• Nephrology
• Pharmacology
• Animal Research

Background:

• Glomerular filtration rate (GFR) is a key indicator of kidney function.
• Accurate GFR measurement is crucial for diagnosing and managing renal diseases.
• Traditional GFR assessment methods can be invasive and stressful, particularly in animal models.

Purpose of the Study:

• To evaluate a novel single-sample method for estimating GFR in conscious rabbits.
• To compare the accuracy of iodixanol-based GFR estimation with the established inulin clearance method.
• To assess the utility of serum urea nitrogen and creatinine as biomarkers for reduced GFR.

Main Methods:

• Co-administration of iodixanol and inulin intravenously in New Zealand White rabbits.
• Blood sample collection at 30, 60, 90, and 120 minutes post-administration.
• Quantification of serum iodixanol and inulin concentrations using HPLC and colorimetry.
• Determination of serum urea nitrogen and creatinine levels.

Main Results:

• GFR estimates using iodixanol showed strong consistency with inulin-based measurements in both healthy and cisplatin-treated rabbits.
• Elevated serum creatinine levels correlated with a GFR decrease exceeding 60% of the reference value.
• Serum urea nitrogen concentrations displayed significant variability, likely due to differing renal handling mechanisms.

Conclusions:

• The single-sample iodixanol method provides a reliable and convenient alternative for GFR estimation in rabbits.
• This method minimizes animal stress associated with multi-sample procedures.
• The iodixanol-based approach is a valuable tool for both clinical and research applications in nephrology.