The circadian rhythm of the content of corticosteroids and of pain sensitivity in humans and rats

: The circadian relationships between blood corticosteroids and latent period of pain reaction to hot stimulation were investigated in man and rats. There were no correlation of blood corticosteroids levels and pain latent period but the latent period increased during those time of day when the corticosteroids levels were higher in total: man--morning and day, rats--evening and night.