Mechanism of contraction rhythm homeostasis for hyperthermal sarcomeric oscillations of neonatal cardiomyocytes.

ABSTRACT: The heart rhythm is maintained by oscillatory changes in [Ca²⁺]. However, it has been suggested that the rapid drop in blood pressure that occurs with a slow decrease in [Ca²⁺] preceding early diastolic filling is related to the mechanism of rapid sarcomere lengthening associated with spontaneous tension oscillation at constant intermediate [Ca²⁺]. Here, we analyzed a new type of oscillation called hyperthermal sarcomeric oscillation. Sarcomeres in rat neonatal cardiomyocytes that were warmed at 38-42 °C oscillated at both slow (~ 1.4 Hz), Ca²⁺-dependent frequencies and fast (~ 7 Hz), Ca²⁺-independent frequencies. Our high-precision experimental observations revealed that the fast sarcomeric oscillation had high and low peak-to-peak am

SUBMITTER: Shintani SA 

PROVIDER: S-EPMC7687892 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature