Microliter-ordered automatic blood sampling system for fully quantitative analysis of small-animal PET

Area of Science:

• Nuclear Medicine
• Pharmacokinetics
• Neuroscience

Background:

• Quantitative positron emission tomography (PET) imaging necessitates accurate arterial plasma radioactivity concentrations for kinetic analysis.
• Manual blood sampling in mice PET studies presents challenges including personnel requirements, radiation exposure, and potential collection errors.
• Development of automated systems is crucial for improving efficiency and safety in preclinical PET research.

Purpose of the Study:

• To develop and validate a fully automated blood sampling system (ABDS) for kinetic analysis in mice PET studies.
• To assess the utility of the ABDS for quantitative measurements of cerebral metabolic rate of glucose (CMRglc) in mice.

Main Methods:

• Nine wild-type male mice underwent femoral artery catheterization under anesthesia.
• Arterial blood samples were collected using the automated blood dispensing system (ABDS) following 18F-fluorodeoxyglucose (FDG) injection.
• Radioactivity concentrations were measured using the CD-Well system, and CMRglc was calculated using kinetic modeling.

Main Results:

• The ABDS demonstrated comparable results to manual blood sampling, with no significant differences observed.
• A minor proportional error was noted specifically in plasma measurements.
• The calculated mean CMRglc value in mice was 5.43 ± 1.98 mg/100 g/min, consistent with prior research.

Conclusions:

• The developed automated microliter-ordered blood sampling system (ABDS) is effective for quantitative CMRglc measurements in mice PET studies.
• The ABDS offers a viable alternative to manual sampling, enhancing precision and potentially reducing radiation exposure.