Slowed relaxation of diaphragm in septic rats is associated with reduced expression of sarco-endoplasmic reticulum CA -ATPase genes SERCA1 and SERCA2.

Introduction: The aim of this study was to study the effects of sepsis on diaphragm relaxation properties and the associated expression of sarco-endoplasmic reticulum Ca -ATPase genes SERCA1 and SERCA2.

Methods: Rats were randomized to undergo either sham surgery or cecal ligation and puncture (CLP). Diaphragm isometric relaxation parameters were measured after 24 h. The mRNA expression and protein content of SERCA1 and SERCA2 in diaphragm muscles were determined.

Results: Both diaphragm maximal twitch and tetanus relaxation rates were reduced. Twitch half-relaxation time was prolonged after normalization to half of peak twitch tension. The mRNA expression and protein content of SERCA1 and SERCA2 were decreased.

Conclusions: Slowed relaxation of the diaphragm in septic rats was associated with reduced expression of SERCA1 and SERCA2. Muscle Nerve 54: 1108-1113, 2016.