Commonly used mouse strains have distinct vascular properties.

Area of Science:

• Cardiovascular Physiology
• Animal Models

Background:

• Mice are crucial animal models for human disease research.
• Variability in mouse cardiac function is known, but vascular stiffness differences across strains are unexplored.

Purpose of the Study:

• To investigate mouse strain-dependent differences in vascular stiffness indices.
• To compare C57Bl/6J, 129S, and Bl6/129S inbred mouse strains.

Main Methods:

• Assessed active in vivo and passive ex vivo vascular stiffness.
• Measured pulse wave velocity (PWV) and acetylcholine-induced vasorelaxation.
• Examined aortic wall thickness and layers.

Main Results:

• Distinct differences in vascular stiffness were observed among strains, independent of baseline blood pressure and heart rate.
• 129S mice exhibited higher tensile stiffness and lower PWV; C57Bl/6J mice showed the opposite.
• Female mice consistently had more compliant aortas within each strain.

Conclusions:

• Inbred mouse strains possess distinct intrinsic vascular properties.
• Strain selection and appropriate controls are critical for genetic studies in mice.
• Results may necessitate verification across multiple mouse strains to avoid false positives.