Caspase-3 regulation of diaphragm myonuclear domain during mechanical ventilation-induced atrophy.

ABSTRACT:

Rationale

Unloading the diaphragm via mechanical ventilation (MV) results in rapid diaphragmatic fiber atrophy. It is unknown whether the myonuclear domain (cytoplasmic myofiber volume/myonucleus) of diaphragm myofibers is altered during MV.

Objective

We tested the hypothesis that MV-induced diaphragmatic atrophy is associated with a loss of myonuclei via a caspase-3-mediated, apoptotic-like mechanism resulting in a constant myonuclear domain.

Methods

To test this postulate, Sprague-Dawley rats were randomly assigned to a control group or to experimental groups exposed to 6 or 12 h of MV with or without administration of a caspase-3 inhibitor.

Measurements and main results

After 12 h of MV, type I and type IIa diaphragm myofiber areas were decreased by 17 and 2

SUBMITTER: McClung JM 

PROVIDER: S-EPMC1899279 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature