<qa>  What is the name of the group that found that riluzole was effective inThe treatments for acute unipolar depression have been extensively researched. However, despite the availability of a wide range of antidepressant drugs, clinical trials indicate that 30 to 40 of depressed patients fail to respond to first-line antidepressant treatment, despite adequate dosage, duration, and compliance. Very few studies have examined the efficacy of somatic treatments for the acute phase of bipolar depression. Thus, there is a clear need to develop novel and improved therapeutics for bipolar depression. Recent preclinical studies suggest that antidepressants may exert delayed indirect effects on the glutamatergic system. Clinical data suggests that lamotrigine an inhibitor of glutamate release and the N-methyl-D-aspartate NMDA antagonist ketamine may have antidepressant effects. Finally, our group recently found in two separate studies that the glutamate modulating agent riluzole was effective in treatment-resistant unipolar and bipolar depression Zarate et al 2004. Together, these data suggest that the glutamatergic system may play a role in the pathophysiology and treatment of depression, and that agents, which more directly reduce glutamatergic neurotransmission, may represent a novel class of antidepressants. 