Banca de QUALIFICAÇÃO: LEONARDO LUCAS DO NASCIMENTO SIQUEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : LEONARDO LUCAS DO NASCIMENTO SIQUEIRA
DATA : 17/08/2017
HORA: 09:00
LOCAL: Auditório da Pós-graduação em Biologia Estrutural
TÍTULO:

CYTOARCHITECTONIC AND IMMUNOHISTOCHEMICAL CHARACTERIZATION AGAIST TYROSINE-HYDROXYLASE IN THE MIDBRAIN NEURONAL NUCLEI OF SEA TURTLES

PALAVRAS-CHAVES:

Chelonia mydas; nervous system; cytoarchitecture; neurotransmitters

PÁGINAS: 40
GRANDE ÁREA: Ciências Biológicas
ÁREA: Morfologia
SUBÁREA: Anatomia
ESPECIALIDADE: Anatomia Animal
RESUMO:

Seven species of sea turtles are known in the world, among them, five species occur on the coast of Brazil: Dermochelys coriacea, Chelonia mydas, Caretta caretta, Eretmochelys imbricata and Lepidochelys olivacea. According to the Red List of the International Union for the Conservation of Nature all species of sea turtles in Brazil are threatened with extinction, with C. mydas classified as "Endangered" and E. imbricata "Critically endangered". The species C. caretta, L.olivacea and D. coriacea are classified as "Vulnerable". Little is known about the neurobiology of these animals. Studies on the external morphology of the nervous system of sea turtles are known, however, works that describe the cytoarchitecture of their brain are nonexistent. This research proposes to characterize the dopaminergic nuclei of the midbrain of sea turtles through a cytoarchitectonic description and by immunohistochemistry for tyrosine hydroxylase (TH). The dopaminergic system plays a critical role in a wide variety of functions and is present in the central nervous system of all vertebrates, being responsible for dopamine neurotransmission. Dopamine is recognized for its activity in the control of complex processes, such as motor activity programming and motivated behaviors. Fifteen specimens of beached sea turtles that died at the Rehabilitation Base of the Projeto Cetáceos da Costa Branca or those found stillborn at the nest openings between the years 2014 to 2017 were used. These animals were necropsied and the brain was removed. The material was fixed in 4% formalin and stored in 30% sucrose for the description of external morphology and microtomy through cryostat. Histological slides of the brainstem sections were made and stained by the Nissl method and/or submitted to immunohistochemistry for TH. The slides were described using an optical microscope and images were taken through a digital camera for documentation through photomicrographs. There were 339 coronal sections of the brainstem of sea turtles. The brainstem in the rostral to caudal direction exhibited the presence of small, rounded catecholaminergic nerve cells located throughout their ventral region in a dispersed form. This preliminary result brings to light differences in the cellular organization of what is observed in other representatives of vertebrates. In this way, we enabled the first descriptions of the dopaminergic system that can aid in the understanding of ecological issues and provide the neuro-anatomic basis for future functional motor studies.

MEMBROS DA BANCA:
Presidente - 1672446 - SIMONE ALMEIDA GAVILAN LEANDRO DA COSTA
Interno - 4363493 - EXPEDITO SILVA DO NASCIMENTO JUNIOR
Interno - 1076490 - FERNANDO VAGNER LOBO LADD