Título:	Heart structure in the Amazonian teleost Arapaima gigas (Osteoglossiformes, Arapaimidae).
Autoria:	GARDINAL, M. V. B. RUIZ, T. F. R. MORON, S. E. YOSHIOKA, E. T. O. GONÇALVES, L. U. VICENTINI, I. B. F. VICENTINI, C. A.
Afiliação:	MARIO VITOR BUZETE GARDINAL, UNESP THALLES FERNANDO ROCHA RUIZ, UNESP SANDRO ESTEVAN MORON, UFT ELIANE TIE OBA YOSHIOKA, CPAF-AP LIGIA URIBE GONÇALVES, INPA IRENE BASTOS FRANCESCHINI VICENTINI, UNESP CARLOS ALBERTO VICENTINI, UNESP.
Ano de publicação:	2019
Referência:	Journal of Anatomy, v. 234, n. 3, p. 327-337, 2019.
Conteúdo:	The fish heart ventricle has varied morphology and may have a specific morpho-functional design in species adapted to extreme environmental conditions. In general, the Amazonian ichthyofauna undergoes constant variations in water temperature, pH and oxygen saturation, which makes these species useful for investigations of cardiac morphology. Arapaima gigas, a member of the ancient teleost group Osteoglossomorpha, is one of the largest freshwater fish in the world. This species has a specific heart metabolism that uses fat as the main fuel when O2 supplies are abundant but also can change to glycogen fermentation when O2 content is limiting. However, no information is available regarding its heart morphology. Here, we describe the heart of A. gigas, with emphasis on the ventricular anatomy and myoarchitecture. Specimens of A. gigas weighing between 0.3 and 4040 g were grouped into three developmental stages. The hearts were collected and the anatomy analyzed with a stereomicroscope, ultrastructure with a scanning electron microscope, and histology using toluidine blue, Masson's trichrome and Sirius red stains. The ventricle undergoes morphological changes throughout its development, from the initial saccular shape with a fully trabeculated myocardium and coronary vessel restricted to the subepicardium (Type I) (group 1) to a pyramidal shape with mixed myocardium and coronary vessels that penetrate only to the level of the compact layer (Type II) (groups 2 and 3). The trabeculated myocardium has a distinct net-like organization in all the specimens, differing from that described for other teleosts. This arrangement delimits lacunae with a similar shape and distribution, which seems to allow a more uniform blood distribution through this myocardial layer.
Thesagro:	Peixe de Água Doce Pirarucu Anatomia Animal
NAL Thesaurus:	Arapaima gigas Freshwater fish Myocardium Anatomy and morphology Heart ventricle
Digital Object Identifier:	10.1111/joa.12919
Tipo do material:	Artigo de periódico
Acesso:	openAccess
Aparece nas coleções:	Artigo em periódico indexado (CPAF-AP)