Neurostimulation is a therapy based in the chemical or electrical stimulation of the brain nuclei, which can generate variations in the production of neurotransmitters. The habenula is part of a conserved brain circuit, which has been considered as a target for the treatment of severe depression. However, studies evaluating the effects of electrical stimulation in the habenula are scarce. The object of the present study is to assess the effect of electrical stimulation of the habenula at different frequencies on the dopaminergic and serotonergic systems in zebrafish. Adult zebrafish were anesthetized, paralyzed and intubated during the deep brain stimulation procedure with frequencies of 20Hz and 130Hz. The stimulation is made with one of two types of microelectrodes: carbon fiber with a diameter of 7±0.6 μm and a resistivity of 2±0.3 10-5Ω m and 30 μm diameter gold wire with a tip of 7±2 μm and a resistivity of 1.6±0.1 10-7Ω m. Gold microelectrodes were fabricated by an electrochemical process in 0.5 M NaCl in DI water and the resistivity was determined by 4-point probe. After the stimulation, the fish are evaluated with immunohistochemistry procedures to identify the changes in the expression of tyrosine hydroxylase and tryptophan hydroxylase, the rate limiting enzymes in the production of dopamine and serotonin, respectively. Also, the receptors zD1 and zSER will be studied across the entire brain. Preliminary results show that zebrafish can be paralyzed at a dose of 1.5μg/g of rocuronium and the effects last for about 4 hours. Fish are anesthetized, paralyzed, intubated using a custom-made system and received a craniotomy of 1mm of diameter above the habenular region. The maximum restrictive amplitude voltage in the zebrafish brain is 4V. This study tests the hypothesis that stimulation of the habenula results in changes in expression on the enzymes and receptors of the serotonergic and dopaminergic systems. Studying the mechanisms of the neurostimulation of the habenula is a step toward understanding the effect of neuromodulator that may be beneficial as an adjuvant therapy against neuropsychiatric disorders.