siamese fighting fish blue and redIn a high dose the SSRIs would act in addition to tricyclic antidepressants with the exception that they don’t bind together with many a whole lot of receptors of the muscarinic, histaminergic or dopaminergic type as is the role played by tricyclic antidepressiva. Thus it is feasible that sertraline applied in a high dose by blocking the α2 adrenergic receptors causes the NE neuronal release that is followed by the stimulation of the motivational brain buildings, including the intensification of aggression. The sertraline antiaggressive effect provided on the model of the mirror test of conspecific aggression in Betta splendens males shows that during environmental attention 0. The role of 5 HT in the conspecific aggression of Betta splendens was provided by Clotfelter et al. proving that fluoxetine―an alternate SSRI―acted in an antiaggressive way by intensifying the serotonergic transmission. A single application of 5 HT as well as 8 OH DPAT antagonist of the 5 HT1A receptor reduced the aggression in Betta splendens.