Behavior of Rats in an Open Field Test as a Prognostic Indicator of Corticosterone Levels Before and After Stress

Studies were performed to assess the role of behavioral indicators in an open field test in predicting the blood corticosterone level in stress. The most reliable indicators of behavior in the open field, reflecting a high probability of a significant increase in the corticosterone concentration after 3-h restraint, were a short latent period of first movement and a low level of motor activity. The probability of high corticosterone in normal “unstressed” conditions is reflected by a low level of motor activity and, conversely, a long latent period for the excursion to the central squares of the field.