Effect of bacterial lipopolisaccharide and interleukine 6 on catalepsy and spontaneous locomotion in mice
Catalepsy is a state of pronounced motor inhibition and is found in all vertebrates. The exaggerated form of catalepsy is a syndrome of some grave mental disorders in human. The selective breeding for high predisposition to catalepsy showed that the major gene of catalepsy is located on the distal fragment of chromosome 13 and seems to be associatied with the Il6st gene coding the gp130 protein, which is the shared protein in the signal transduction from interleukins, participating in the cell differentiation, immune and endocrine regulation. Experiments were carried out on adult C57BL/6J catalepsy-resistant mouse males. Bacterial lipopolysaccharide (LPS; 100, 200 μg/kg, i.p.) signifi cantly depressed all activity in the open-fi eld and it induced cataleptic immobility (more than 20 s three times) in 50% of mice in each group. Interleukine 6 (IL-6; 200ng/mouse, i.p.) did not effect on behavior in openfi eld, but it induced immobility in 70% of mice. Administration of LPS or IL-6 increases the level of IL-6 which binds to the IL-6 receptor, this reaction results to activation of gp130 protein. So, caleptogenic effect of LPS and IL-6 is in good correlation with association of predisposition to catalepsy with Il6st gene. Since depressive-like behavior and immunity disturbances were found in mice selected for catalepsy and LPS treatment could model depression, gp130 protein seems to be involved in regulation of both depression and catalepsy.