Identification Of Differentially Expressed Genes After Heat Shock In Isolated Rat Aorta

1. In a previous study, we demonstrated that heat shock augments vascular contractility through the stress response.2. The current study was designed to identify differentially expressed genes after heat shock by using a novel annealing control primer (ACP) system, which was developed recently to identify authentic genes.3. Rat aortic rings were mounted in organ baths, exposed to 42 degrees C for 45 min and harvested 4 h after the end of heat shock. Total RNA were used for amplification by the reverse transcriptase-polymerase chain reaction (RT-PCR) with ACP system. Differentially amplified PCR products were sequenced, searched against the GenBank and confirmed by RT-PCR.4. Genes for connective tissue growth factor, stress-inducible protein 1 and heat shock protein 25 were upregulated, whereas a gene for interferon regulatory. factor 1 was downregulated. Immunohistochemistry revealed upregulation of the phosphorylated form of Hsp25 in aortic rings after heat shock.5. These results suggest that phosphorylated Hsp25 plays a pivotal role in the augmentation of vascular contraction after heat shock.