Zwanzger, P.; Schule, C.; Eser, D.; Baghai, Thomas C.; Padberg, F.; Ella, R.; Möller, Hans-Jürgen; Rupprecht, R.; Kathmann, N.
Saccadic eye velocity after selective GABAergic treatment with tiagabine in healthy volunteers.
In: Neuropsychobiology, Nr. 3: S. 147-150
Background: Saccadic eye velocity (SEV) has been shown to be a reliable neurophysiological tool for the assessment of gamma-aminobutyric acid GABA(A) receptor sensitivity. Administration of benzodiazepines targeting the GABA(A) receptor decreases SEV in healthy volunteers. Tiagabine is a new antiepileptic drug which acts via selective blockade of GABA reuptake. Therefore, we examined the effects of tiagabine on saccade parameters. Methods: SEV was analyzed in 8 healthy volunteers before and after 7 days of tiagabine treatment. Subjects received tiagabine in a daily dose of 15 mg. Saccades were measured using a noninvasive infrared oculographic device. Amplitude, latency, and SEV were analyzed as a function of treatment and target eccentricity. Results: SEV and saccade latency increased with target amplitude. Treatment with tiagabine had no significant effect on SEV and saccade amplitude. A trend was found for increased latencies after tiagabine. Conclusion: In contrast to findings with benzodiazepines, tiagabine treatment had no impact on SEV in healthy volunteers. The subchronic tolerance effects or the different site of action on the GABA(A)/BZD receptor complex may account for this deviating profile. Copyright (C) 2005 S. Karger AG, Basel.