Effects of sibutramine and methylphenidate in an animal model of Attention Deficit Hyperactivity Disorder (ADHD) induced in mice by ethanol in the postnatal period

Author(s)

Everton Barbosa Bertaglia

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2017-03-31

Examining board members

Helenice de Souza Spinosa; André Rinaldi Fukushima; Milena Rodrigues Soares

• Advisor: Helenice de Souza Spinosa

Abstract

The attention deficit hyperactivity disorder (ADHD) is a condition that can be characterized by the lack of attention, impulsivity and hyperactivity. The pathophysiology of ADHD is related mainly to changes in the dopaminergic system, noradrenergic and serotoninergic of central nervous system. Among the treatments used stands out the pharmacotherapy with methylphenidate, potential drug of abuse, which acts as an inhibitor of the reuptake of dopamine, noradrenaline and serotonin; on the other hand, the salt of sibutramine monohydrate, which has a pharmacological mechanism of action similar in these systems of central neurotransmission, have not had their use tested in a model of ADHD. Thus, the objective of this work was to study the effects of prolonged administration (28 - 32 days) of sibutramine and methylphenidate in an animal model of ADHD induced by exposure to ethanol in the postnatal period in mice, evaluating the weight gain weekly, the consumption of water and feed, as well as animal behavior, through the general assessment in open field, and in the elevated plus maze, and in the tests of tail suspension, the recognition of objects and the T maze. We evaluated the levels of neurotransmitters and their metabolites in different brain structures. The results showed that the animal model of ADHD induced by exposure to ethanol in the postnatal period showed hypoactivity in the open field followed by increased activity, showed no changes in the levels of anxiety in the elevated plus maze, as also shown depressive-like behavior in the tail suspension test and striking deficit in working memory and attention in the test of recognition of objects and T maze. In relation to the prolonged treatment with sibutramine and methylphenidate, no alterations were observed in weight gain weekly, and consumption of water and food. In the open field, methylphenidate normalized the activity of mice, while sibutramine caused hyperactivity. In the elevated plus maze no changes were observed in anxiety levels. In the tail suspension test methylphenidate caused depressive-like behavior in mice salina, while sibutramine reversed the effects of depression of ethanol. Methylphenidate has improved the working memory and attention of mice that received ethanol both in the test of recognition of objects as the maze in T, since sibutramine was able to do it only in the maze in T. (AU)