Heat shock proteins (Hsps) responses against stress conditions. Melatonin completes its stress relieving activities via its MT1 and MT2 receptors. The present study delineates the expression pattern of Hsp70/Hsc70 and MT1/MT2 receptor proteins along with the AANAT gene expression in the splenic tissue of mice subjected to hyperthermic stress in a temperature dependent and time dependent manner. In vivo thermal stress resulted increase in expression of Hsp70, Hsc70 and MT2 receptors proteins in both temperature dependent and time dependent manner. Optimum heat exposure at 430C and maximized Hsps expression was observed after 5 hours of heat exposure. Heat stress caused increase in AA-NAT gene expression of the splenic tissue resulted in the synthesis of melatonin which might act as signal molecule for upregulating the activity and rise of the stress responsive genes and proteins like: Hsp70/Hsc70, whereas simultaneous increase of MT2 expression shows its possible involvement in such mechanism.
Key words: Thermal stress, heat shock proteins, melatonin receptors, AA-NAT gene expression, time and temperature dependent study in mice