Guinea-pig atrial cardioballs.

Area of Science:

• Cardiovascular Physiology
• Cell Biology
• Electrophysiology

Background:

• Dispersed cardiac myocytes are crucial for studying cellular electrophysiology.
• Maintaining cell viability and function after isolation presents significant challenges, particularly calcium (Ca) intolerance.

Purpose of the Study:

• To establish a reliable method for isolating and culturing adult guinea-pig atrial myocytes.
• To overcome the issue of calcium intolerance in isolated myocytes.
• To prepare myocytes in a suitable format for advanced electrophysiological recordings.

Main Methods:

• Enzyme perfusion of adult guinea-pig atria with modifications.
• Controlled temperature (not below 25°C) and gradual calcium (Ca) increase during perfusion.
• Long-term cell culture leading to spherical myocyte formation ('cardioballs').
• Patch clamp techniques, including tight-seal whole-cell recording with dialysis.

Main Results:

• Successfully isolated viable atrial myocytes from adult guinea-pigs.
• Circumvented calcium intolerance through modified isolation and perfusion protocols.
• Developed 'cardioballs' – spherical myocytes stable in culture for approximately 10 days.
• Demonstrated suitability of 'cardioballs' for patch clamp electrophysiology.

Conclusions:

• The modified enzyme perfusion and culture method yields viable atrial myocytes.
• The 'cardioball' morphology is advantageous for patch clamp studies.
• This technique provides a robust model for investigating atrial myocyte electrophysiology.