Immobilization stress induces c-fos and c-jun immediate early genes expression in the heart.

Emotional stress is considered to be one of the etiological factors in ischemic heart disease (IHD) and sudden cardiac death (SCD), mechanisms of which are poorly understood. Immediate early genes (IEGs), such as c-fos and c-jun are used as tools for detection of cellular activation. Male Wistar rats were exposed to acute immobilization (IMO). IMO stress for 30 min induced c-fos and c-jun mRNAs expression in the myocardium and the smooth muscle layer of the coronary arteries. IMO stress for 2 h also induced Fos and Jun like-immunoreactivities in the same regions. Distribution of IEG mRNAs and their protein products in the myocardium was not uniform but rather localized. These data provided histological evidence for an early cellular event in the stress response whose consequences could result in activation of tissues in the myocardium and coronary arterial smooth muscle cells which play a role in the pathophysiological changes in IHD and SCD.