Hsp32 (haeme-oxygenase 1) induction has been previously reported to provide protection against pulmonary hypertension in a non-diet murine model 9, and induction of Hsp70 in the rat lung by heat exposure can attenuate lung fibrosis 10, The role of Hsp90 in the regulation of lung fibrosis is not clear, but a recent review suggests that it could be a promoter of cystic fibrosis 11. This evidence concerns the gene HMOX1 and pulmonary fibrosis.