Conclusions
Our data implicate that MV causes endothelial activation and inflammation in mice without pre-existing pulmonary injury, both in the lung and distal organs.
Methods
Healthy male C3H/HeN mice were anesthetized, tracheotomized and mechanically ventilated for either 1, 2 or 4 hours. To study the effects of alveolar stretch in vivo, we applied a MV strategy that causes overstretch of pulmonary tissue i.e. 20 cmH2O peak inspiratory pressure (PIP) and 0 cmH2O positive end expiratory pressure (PEEP). Non-ventilated, sham-operated animals served as a reference group (non-ventilated controls, NVC).
Results
Alveolar stretch imposed by MV did not only induce de novo synthesis of adhesion molecules in the lung but also in organs distal to the lung, like liver and kidney. No activation was observed in the brain. In addition, we demonstrated elevated cytokine and chemokine expression in pulmonary, hepatic and renal tissue after MV which was accompanied by enhanced recruitment of granulocytes to these organs. Conclusions: Our data implicate that MV causes endothelial activation and inflammation in mice without pre-existing pulmonary injury, both in the lung and distal organs.