In the field of preclinical research, precision, reproducibility, and ethical responsibility are paramount. When it comes to pharmacokinetic (PK) and toxicokinetic (TK) studies, catheterized rodents—especially rats and mice—offer significant advantages over traditional sampling methods. By enabling repeated blood sampling and compound administration from a single animal, catheterization enhances data quality while reducing animal usage, aligning with both scientific and ethical goals.

Enhanced Data Quality and Consistency

One of the core benefits of catheterization is the ability to collect high-resolution time-course data from a single animal. This significantly reduces inter-animal variability and allows for:

  • More accurate PK profiles

  • Reduced standard deviations across sampling points

  • Improved statistical power with fewer animals

This approach is especially valuable in studies involving narrow therapeutic windows or compounds with complex absorption and elimination profiles.

Reduction in Animal Use (3Rs Compliant)

By using catheterized animals, multiple blood samples can be drawn from the same subject—reducing the number of animals required per study. This supports the 3Rs principle (Replacement, Reduction, and Refinement) and reflects a more ethical approach to preclinical study design.

  • Fewer animals required per group

  • Longitudinal studies possible in the same subject

  • Supports regulatory expectations for animal welfare

Minimally Invasive Sampling & Reduced Stress

Repeated tail vein or retro-orbital sampling can introduce stress and variability, potentially confounding PK/TK data. With properly maintained catheters, blood samples and infusions can be performed with minimal restraint and lower stress levels.

  • Less handling during each timepoint

  • Reduced physiological impact on study animals

  • More stable data for sensitive compounds

Flexibility in Study Design

Catheterized rodents allow for automated dosing, blood sampling, and even multi-compartment infusion or sampling(e.g., dual catheter setups). This enables more complex and customized study designs such as:

  • Constant-rate intravenous infusion

  • Serial sampling for plasma, bile, or urine

  • Push-pull sampling for maintaining blood volume balance

Regulatory and Industry Acceptance

Many CROs, sponsors, and regulatory agencies recognize the value of catheterized models in providing high-quality kinetic data. Whether for IND-enabling studies or mechanistic evaluations, catheterization is often considered a gold standard method in rodent-based kinetic studies.

Conclusion

Catheterized rodent models offer a unique combination of precision, animal welfare, and operational efficiency. As preclinical research continues to demand more data from fewer animals, this approach stands out as a scientifically robust and ethically responsible solution.

Whether you’re conducting exploratory PK studies or preparing for regulatory submissions, incorporating catheterized rodent models can provide the confidence and clarity your research needs.

Interested in improving your PK/TK workflows with catheterized models? Contact our team to learn more about our preclinical solutions.

www.prasurgical.com

info@prasurgical.com