Banca de DEFESA: SARAH SOPHIA GUEDES LINHARES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : SARAH SOPHIA GUEDES LINHARES
DATA : 28/03/2019
HORA: 09:00
LOCAL: Sala Darwin
TÍTULO:

Behavioral and neurochemical evaluation of components of the timing system in male and female Wistar rats exposed to perinatal treatment with fluoxetine

PALAVRAS-CHAVES:

fluoxetine, perinatal, circadian rhythm, neuropeptide Y, serotonin

PÁGINAS: 29
GRANDE ÁREA: Ciências Humanas
ÁREA: Psicologia
RESUMO:

Selective serotonin reuptake inhibitors (SSRIs) are most commonly prescribed psychotropic drug during pregnancy and lactation. In this sense, it exposes mothers and infant brain to up modulatory and trophic effects of serotonergic neurotransmission. The serotonin promotes fundamental changes across development which include neuron migration, differentiation and organization of brain circuitry related to emotional, cognitive and circadian behavior. Early exposure to the selective serotonin reuptake inhibitors (SSRIs) induce long-lasting effects on behavioral and neural signalization of rodents. These effects include increased anxiety and depression-like behavior in adulthood and also aberrant neural circuit formation during lifespan. However, the long-term effects of early exposure to antidepressant over circadian rhythms and their neurochemical markers remain unclear. In this study, we tested the locomotor activity-rest rhythm, anxiety-memory performance and chemical oscillatory markers of the circadian system (neuropeptide Y and serotonin) at two zeitgebers (ZT6 and ZT18) in male and female offspring rats early exposed (developmental period GD13-GD21) to fluoxetine (20mg/kg). First, we carry out daily records of the locomotor activity-rest rhythm using activity sensors coupled to individual cages over four weeks. Then, we tested the anxiety-trace and memory behaviour using the open field chamber (OF) and discriminative avoidance (DA) paradigms. We lastly identify the neuropeptide Y (NPY) expression labelling both suprachiasmatic nucleus and intergeniculate leaflet (IGL), and as well the serotonin (5-HT) expression in the dorsal and medial raphe nuclei. In summary our results showed (1) perinatal fluoxetine affect anxiety and memory behaviour only in female rats (2) perinatal fluoxetine affect NPY and 5-HT expression and phase entrainment of locomotor circadian rhythm at ZT6 and ZT18 more in male than female offspring. Our data concur with previous reports had been showing that perinatal fluoxetine treatment do not elicit anxiety-trace and memory deficits in male rats although we have shown differential effects in females. The sexual differences induced by early exposure to fluoxetine on both locomotor circadian rhythm abnormalities and neurochemical expression are an important highlight of present work. Here, we show that male rats are more susceptible of phase entrainment and the NPY and 5-HT mis-expression compared to female rats. Thus, our results may helpful to a better knowledge about neurobiological mechanisms of circadian rhythms and relevant to understand the “broken brains” and behavioural abnormalities of offspring early exposed to antidepressants.

MEMBROS DA BANCA:
Externo à Instituição - EZEQUIEL BATISTA DO NASCIMENTO
Presidente - 2351800 - JEFERSON DE SOUZA CAVALCANTE
Interna - 1718518 - NICOLE LEITE GALVAO COELHO