Effect of intranasal administration of thyrotropin-releasing hormone on ataxic gait in staggerer mice

Abstract

The ataxia ameliorating effect of an intranasal administration of thyrotropin-releasing hormone (TRH) was examined using normal and ataxic staggerer mutant mice. In the normal mice, the blood TRH level reached the maximum level 5 min after administration and was gradually eliminated during the following 60 min. The antiataxic effects of TRH in the staggerer mice was examined using an open field method. At lower doses, the intranasal administration of TRH did not exert any evident effect. However, at 3 mg or 4 mg, the fall index (the ratio of the number of falls to the movement score) was significantly decreased for 20 min after the administration. These results show that an intranasal administration of TRH can ameliorate the ataxia in staggerer mice, and may be promising for clinical use in patients with spinocerebellar degeneration.