Anxiolytic- and antidepressant-like effects of an antagonist at glycineB receptors.

L-701,324 [7-chloro-4-hydroxy-3-(3-phenoxy)phenyl-2-(1H)-quinolone], a selective antagonist at glycineB receptors, was studied in behavioral tests used to predict a potential anxiolytic (conflict drinking test in rats, four-plate test in mice) and antidepressant (forced swimming test in rats and mice) activity. In the conflict drinking test in rats, L-701,324 (0.5 mg/kg, but not 0.25 and 1 mg/kg) increased the number of punished licks in a statistically significant manner. In the four-plate test in mice, L-701,324 (2 mg/kg, but no lower doses) significantly increased the number of punished crossings. In the forced swimming test in rats, L-701,324 (0.5 mg/kg) slightly, but statistically significantly, reduced the immobility time; the drug was inactive in doses of 0.25 and 1 mg/kg. In mice, L-701,324 administered only in the highest dose used (2 mg/kg) significantly shortened the immobility time. L-701,324 (given in doses higher then 2 mg/kg) induced motor impairment in animals. The above findings indicate that L-701,324 shows weak anxiolytic- and antidepressant-like activities in the animal models used.