32 Effect of classic preconditioning on the gene expression pattern of rat hearts: a DNA microarray study

To pro¢le gene expression patterns involved in ische- mic preconditioning, we monitored global gene expression changes by DNA microarray analysis of 3200 rat-speci¢c genes and by real-time quantitative polymerase chain reaction in rat hearts. Forty-nine genes with altered expression were found after ischemia/reperfusion as compared to control non-ischemic hearts and 31 genes were characteristic for classic precondition- ing followed by ischemia/reperfusion as compared to ischemia/ reperfusion without preconditioning. Genes with altered expres- sion due to ischemia and/or preconditioning included those con- trolling protein degradation, stress responses, apoptosis, meta- bolic enzymes, regulatory proteins, and several unknown cellular functions. Metallothionein, natriuretic peptides, coagulation fac- tor VII, cysteine proteinase inhibitor, peroxisome proliferator activator receptor Q and myosin light chain kinase genes were previously suspected to be related to several cardiovascular dis- eases, however, most of these genes have not previously been shown to be related to myocardial ischemia/reperfusion. Some genes were observed to change speci¢cally in response to pre- conditioning: oligoadenylate synthase, chaperonin subunit O ,a cGMP phosphodiesterase (PDE9A1), a secretory carrier mem- brane protein, an amino acid transporter, and protease 28 sub- unit. None of these genes has previously been shown to be in- volved in the mechanism of preconditioning. 4 2003 Federation of European Biochemical Societies. Pub- lished by Elsevier Science B.V. All rights reserved.