Four studies made models on the basis of underlying pathogenesis of depression, included IA models22 (IA can simulate effects of the endogenous excitatory amino acids on the onset of depressive symptoms), L-AAA models (L-AAA can destroy astrocytes)64, EAAT1 antagonist models and EAAT2 antagonist models77 (EAAT1 and EAAT2 antagonist can inhibit functions of glutamate transporter). The gene discussed is SLC1A2; the disease is major depressive disorder.