Male neonatal rat ventricular myocyte monolayers generated significantly higher systolic and diastolic contractile stress than female monolayers at matched seeding densities under identical in vitro conditions.
Do male and female neonatal rat ventricular myocytes exhibit intrinsic structural and functional differences when cultured in vitro under identical conditions?
In vitro neonatal rat ventricular myocytes exhibit intrinsic, sex chromosome-driven differences in tissue architecture and contractile function, providing a platform to study sex-specific cardiac physiology independent of hormonal influences.
Effect estimate: Male monolayers generated significantly higher systolic and diastolic stress than female monolayers at low and mid seeding densities (P<0.05)
p-value: P<0.05
Even though in vivo rodent studies have been instrumental in investigating sex-specific differences in cardiac health, function, and pathology, they fall short in providing a fast and flexible platform for investigating sex differences of cardiac anisotropic monolayer in isolation. In vitro platforms offer an accessible and more controlled alternative to dissect and study the mechanisms by which male and female cardiac tissue sheets differ from one another. Here, we have shown on an in vitro heart-on-a-chip platform, primary neonatal rat ventricular myocytes can serve as a viable model showing sex chromosome-driven characteristics when presented with identical experimental conditions. With controlled experimental conditions, the self-assembly of isolated cardiomyocytes resulted in morphological differences in the structure of the contractile apparatus. More importantly, the assembly of cardiac cells into confluent monolayers had a sex chromosome-driven divergence in both structure and the corresponding function. This work reports the characterization of the difference between sex-specific neonatal rat ventricular myocytes in in vitro culture. Thus, this offers an avenue to investigate sex-based variations in cardiac function that are otherwise difficult to study.
Tran et al. (Thu,) conducted a other in Neonatal rat ventricular myocytes isolated from male-only or female-only two-day old Sprague-Dawley rat pups. Sex-specific neonatal rat ventricular myocytes cultured as confluent monolayers on fibronectin patterned heart-on-a-chip platform vs. Male versus female neonatal rat ventricular myocyte cardiac sheets was evaluated on Contractile function measured as systolic and diastolic stress generation of cardiac monolayers at varying seeding densities (Male monolayers generated significantly higher systolic and diastolic stress than female monolayers at low and mid seeding densities (P<0.05), p=P<0.05). Male neonatal rat ventricular myocyte monolayers generated significantly higher systolic and diastolic contractile stress than female monolayers at matched seeding densities under identical in vitro conditions.