Human tissue samples
Cardiac samples were obtained from 6 organ donors (2 male) at the
University of Kentucky (Table 1). Their mean age was 45.5 (range 10-61)
years. As previously described in detail (Blair et al., 2016), hearts
were passed to a researcher as soon as they were excised from the body,
immediately placed in ice cold saline slush and transported back to the
laboratory where tissue samples (~500 mg) were snap
frozen in liquid nitrogen and stored at -150°C within
~20 minutes. Mid-myocardial sections of the left
ventricular free wall were shipped overnight on dry ice to Washington
State University and stored at -80°C for 1-3 weeks, until they were
dissected for mechanics and biochemical experiments. All procedures were
approved by the University of Kentucky Institutional Review Board.