Banca de DEFESA: VIVIANE FELINTRO DE SOUZA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : VIVIANE FELINTRO DE SOUZA
DATA : 09/03/2018
HORA: 09:00
LOCAL: Sala 1 - PQ
TÍTULO:

Effect of intracellular thirst on behavioral responses in rats
submitted to water deprivation and salt loading: Possible role of AVPR1a and
OTR receptors.

PALAVRAS-CHAVES:

Thirst, water deprivation, salt loading, anxiety, vasopressin type 1a
receptor, oxytocin receptor.

PÁGINAS: 89
GRANDE ÁREA: Ciências Biológicas
ÁREA: Fisiologia
SUBÁREA: Fisiologia Geral
RESUMO:

Thirst is an essential sensation for the development behavioral changes that driving the
motivation for drink water, a vital response for the maintenance of hydrosaline
homeostasis. Animals that are submitted to water or food deprivation in general are
more willing to take risks for their survival, in this sense, water deprivation and salt
loading were stimuli used to trigger intracellular thirst. Under these conditions
vasopressin (AVP) and oxytocin (OT) are secreted by magnocellular neurons through
the neurohypophysis and release for the systemic circulation. Namely, recent studies
have demonstrated that vasopressinergic magnocellular neurons project to
extrahypothalamic regions, which include the habenula and amygdala. Thus, the present
study aimed to analyze the effect of increased plasma osmolality on exploratory and
anxiety-like behaviors in rats subjected to water deprivation and salt loading, as well as
evaluating the gene expression of type 1a AVP (AVPR1a) and OT (OTR) receptors in
the basolateral amygdala, central amygdala and habenula, as well as the enzyme
synthesizing GABA (GAD67) and the glutamate vesicular transporter (VGLUT2) in
both nuclei. Male Wistar rats were randomly divided into five experimental groups:
Control (CT), 24 hour water deprivation (PH24h) and 48 hours (PH48h) and salt
loading with 1.8% NaCl for 24 hours (SS24h) and 48 hours (SS48h). All groups were
submitted to plasma analysis, behavioral tests and analysis of gene expression through
RT-qPCR. All data are described as mean ± standard error of the meanand the
differences were considered significant when p < 0.05. Plasma osmolality increased
significantly in the PH48h (p = 0.0039) and SS48h (p = 0.0176) groups. In the elevated
plus maze, there was increase in the percentage of open arm entries in groups PH48 (p =
0.0079) and SS48h (p = 0.0015), as well as the time spent in open arms in PH48h (p =
0.0029) and SS48h (p <0.0001), indicating an anxiolytic response. In addition, linear
regression was significant between plasma osmolality vs time spent in the open arms (p
= 0.0004, r = 0,259). In the open field no difference was observed, indicating that the
animals did not increase the spontaneous locomotor activity. In the light and dark box,
only the PH48h group (p = 0.0424) showed an increase in time spent in the light area. In
relation to gene expression, we observed a significant increase in the expression of
AVPR1a (p = 0.0345) and OTR (p = 0.0103) in the PH48h group in the central
amygdala. Our results indicate that plasma hyperosmolarity induced by 48 hours of
water deprivation or salt loading is capable of eliciting anxiolytic behaviors in rats and
it’s possible that AVPR1a and OTR receptors mediate this response in the central
amygdala.

MEMBROS DA BANCA:
Presidente - 2778889 - ANDRE DE SOUZA MECAWI
Interno - 1519567 - FABIO FAGUNDES DA ROCHA
Externo à Instituição - DANILO LUSTRINO BORGES - UFS