Effect of acute stresses on Zn-thionein production in rat liver

Male Wistar strain rats were exposed to acute stress from broad-band noise [100 dB (A) for 1 h] or cold (4 degrees C for 24 h). Following exposure to noise for 1 h, serum and adrenal gland showed about 1.8 times and 2.5 times the corticosterone levels of the control group, but this enhancement was not observed after exposure to cole. Both stresses increased Zn-thionein significantly in the liver. Furthermore, the two stresses increased the content of Zn in the 30,000 g supernatant fraction of the liver, though serum Zn concentration was not altered. It is believed that thionein is a regulatory protein with a specific function for Zn metabolism in organs. Although it is known that corticosterone affects Zn metabolism in man and animals, there is little investigation of the effect of environmental stresses on Zn metabolism. The present data suggest that Zn metabolism may be important in the investigation of the effects of repeated and long term exposure to environmental stresses involving noise and cold.