masterThesis
Avaliação da dinâmica neuronal do núcleo paraventricular do hipotálamo durante o desenvolvimento pós-natal em cutia (Dasyprocta aguti - Linnaeus, 1766.)
Fecha
2020-03-07Registro en:
LANDIM, Raíssa Tainá Fernandes. Avaliação da dinâmica neuronal do núcleo paraventricular do hipotálamo durante o desenvolvimento pós-natal em cutia (Dasyprocta aguti - Linnaeus, 1766.). 2020. 82f. Dissertação (Mestrado em Biologia Estrutural e Funcional) - Centro de Biociências, Universidade Federal do Rio Grande do Norte, Natal, 2020.
Autor
Landim, Raíssa Tainá Fernandes
Resumen
The hypothalamus is a central nervous system (CNS) region, composed of
several nuclei responsible for maintaining homeostasis. Among many hypothalamic
nuclei there is the Paraventricular nucleus (PVN), which is one of the centers
responsible for the autonomic and endocrine regulation of the organism. PVN is an
important pre-autonomic center that assists in the regulation of the sympathetic
nervous system, acting at the regulation of several systems, including the
cardiovascular system. Changes in this nucleus may be related to cardiovascular
complications, such as hypertension and heart failure. Therefore, with aging, there may
be changes in PVN that can trigger cardiac changes in the elderly. Thus, we analyzed
the PVN of agouti (Dasyprocta agouti) in different ages in order to observe the neuronal
dynamics in the nucleus during the postnatal development. For this, three-dimensional
morphoquantitative analysis (stereological analysis) of the PVN was performed, based
on Cavalieri’s principle, together with the volume density (Vv) analysis of the nucleus
neurons based on Delesse’s principle, quantification of number of neurons by optical
dissector and average neuronal volume per nucleator. These analyzes were performed
in 11 male agoutis, divided into four age groups: G1- Neonate (n = 2); G2- Young (n =
2); G3- Adult (n = 3) and G5-Senile (n = 4). In the PVN of the agouti two magnocellular
regions and six parvocellular regions were observed. Quantitative analysis showed
that the PVN of senile animals, when compared to neonates, shows a 317% increase
in total nucleus volume and 291% increase in total volume occupied by non-neuronal
components. It also showed that the number of young and senile neurons, when
compared with neonates, had a 114% increase. For adults, when compared with
neonates, had a 109% increase. Therefore, our data indicate that PVN of senile agouti
presents hypertrophy and may be associated with neuronal hyperplasia when
compared to neonates.