Role of the distal fragment of chromosome 13 in the regulation of IL-6-induced effect on the behavior of mice.

We studied the effect of IL-6 on the open-field behavior and degree of cataleptic freezing in male AKR/J mice and AKR.CBA-D13Mit76 congenic animals (differing from CBA/Lac mice in the chromosome 13 fragment of 111.35-116.14 Mbp). IL-6 in both doses significantly increased the time of cataleptic freezing. IL-6 in a dose of 3 μg/kg had a strong inhibitory effect on locomotor activity of AKR.CBA-D13Mit76 males in the open-field test. However, IL-6 in both doses did not modulate locomotor activity and severity of catalepsy in AKR/J males. Our results indicate that the distal fragment of chromosome 13 is involved in the effect of IL-6 on the locomotor activity of mice.