5HT(2C) receptor agonists exhibit antidepressant-like properties in the anhedonia model of depression in rats

Potential antidepressant properties of preferential 5HT(2c) receptor agonists were investigated in stress-induced anhedonia, a validated simulation of depression. This simulation evaluates the hedonic state of stressed rats by recording variations in self-stimulation threshold measured before, during, and after exposure to intermittent, unpredictable, mind stressors. This stress regimen gradually elevates self-stimulation threshold, suggesting the development of an anhedonic state. In stressed animals, chronic treatment with the preferential 5HT(2C) receptor agonists Ro 60-0175 and Ro 60-0332 (3 mg/kg i.p, b.i.d.) prevented the loss of sensitivity to reward. Similarly, when stressed anhedonic animals were curatively treated with Ro 60-0175 (3 mg/kg i.p. b.i.d.), the stress-induced anhedonia was gradually reversed. These results suggest a role for 5HT(2C) receptors in some aspects of depression, and potential antidepressant properties for selective 5HT(2C) receptor agonists. Such compounds may offer an innovative approach to the treatment of mood disorders.