Trabalho Apresentado em Evento

The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)

Nitrite oxidizes haemoglobin (Hb) to methaemoglobin (MetHb), which is unable to bind oxygen. Nitrite exposure can therefore be used as a tool to manipulate the oxygen-carrying capacity of the blood without changing haematocrit. The objective of this study is to examine the relationship between the c...

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Autor principal: Val, Adalberto Luis
Outros Autores: Brauner, Colin Jonh
Grau: Trabalho Apresentado em Evento
Idioma: English
Publicado em: Inglaterra 2020
Assuntos:
Truta
Hemoglobinas
Natação
Nitrito
Acesso em linha: https://repositorio.inpa.gov.br/handle/1/23332
id oai:repositorio:1-23332
recordtype dspace
spelling oai:repositorio:1-23332 The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha) Val, Adalberto Luis Brauner, Colin Jonh Truta Hemoglobinas Natação Nitrito Nitrite oxidizes haemoglobin (Hb) to methaemoglobin (MetHb), which is unable to bind oxygen. Nitrite exposure can therefore be used as a tool to manipulate the oxygen-carrying capacity of the blood without changing haematocrit. The objective of this study is to examine the relationship between the critical swimming velocity (Ucrit) and the functional haemoglobin concentration ([Hb]) of the blood in adult chinook salmon. Functional [Hb] was reduced by increasing MetHb levels through intraperitoneal administration of a mass-dependent volume of sodium nitrite. In resting fish, MetHb levels were found to stabilize at 25 % of total [Hb] 3 h after the injection of 30 mg kg-1 sodium nitrite. Methaemoglobin levels increased in proportion to the amount of sodium nitrite injected and reached a maximum (following the injection of 90 mg kg-1 sodium nitrite) of 51.8 % in resting fish and 72 % in fish forced to swim to Ucrit. At 60 and 90 mg kg-1 sodium nitrite, MetHb formation was greater in exercised than in resting fish. A second-order regression revealed that Ucrit was virtually independent of functional [Hb] between 51 and 100 % of control functional [Hb], but was positively correlated with functional [Hb] below 51 % of total [Hb] (4.5 g dl-1). The insensitivity of Ucrit to a functional [Hb] greater than 51 % may be partly due to the exponential increase in aerobic metabolism required to provide the power to overcome hydrodynamic drag at higher water velocities. There were no significant changes in intraerythrocytic organic phosphate (adenylates and guanylates) concentrations standardized to [Hb] in swimming or resting fish over the range of MetHb levels induced in this study. Fish may encounter nitrite naturally; if MetHb levels become severely elevated as a result, swimming ability will be significantly impaired. 2020-07-16T14:46:36Z 2020-07-16T14:46:36Z 1992 Trabalho Apresentado em Evento https://repositorio.inpa.gov.br/handle/1/23332 en Journal of Experimental Biology 1993 185: 121-135 Attribution-NonCommercial-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nc-nd/3.0/br/ application/pdf Inglaterra Annual Meeting of the Society for Experimental Biology
institution Instituto Nacional de Pesquisas da Amazônia - Repositório Institucional
collection INPA-RI
language English
topic Truta
Hemoglobinas
Natação
Nitrito
spellingShingle Truta
Hemoglobinas
Natação
Nitrito
Val, Adalberto Luis
The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)
topic_facet Truta
Hemoglobinas
Natação
Nitrito
description Nitrite oxidizes haemoglobin (Hb) to methaemoglobin (MetHb), which is unable to bind oxygen. Nitrite exposure can therefore be used as a tool to manipulate the oxygen-carrying capacity of the blood without changing haematocrit. The objective of this study is to examine the relationship between the critical swimming velocity (Ucrit) and the functional haemoglobin concentration ([Hb]) of the blood in adult chinook salmon. Functional [Hb] was reduced by increasing MetHb levels through intraperitoneal administration of a mass-dependent volume of sodium nitrite. In resting fish, MetHb levels were found to stabilize at 25 % of total [Hb] 3 h after the injection of 30 mg kg-1 sodium nitrite. Methaemoglobin levels increased in proportion to the amount of sodium nitrite injected and reached a maximum (following the injection of 90 mg kg-1 sodium nitrite) of 51.8 % in resting fish and 72 % in fish forced to swim to Ucrit. At 60 and 90 mg kg-1 sodium nitrite, MetHb formation was greater in exercised than in resting fish. A second-order regression revealed that Ucrit was virtually independent of functional [Hb] between 51 and 100 % of control functional [Hb], but was positively correlated with functional [Hb] below 51 % of total [Hb] (4.5 g dl-1). The insensitivity of Ucrit to a functional [Hb] greater than 51 % may be partly due to the exponential increase in aerobic metabolism required to provide the power to overcome hydrodynamic drag at higher water velocities. There were no significant changes in intraerythrocytic organic phosphate (adenylates and guanylates) concentrations standardized to [Hb] in swimming or resting fish over the range of MetHb levels induced in this study. Fish may encounter nitrite naturally; if MetHb levels become severely elevated as a result, swimming ability will be significantly impaired.
format Trabalho Apresentado em Evento
author Val, Adalberto Luis
author2 Brauner, Colin Jonh
author2Str Brauner, Colin Jonh
title The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)
title_short The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)
title_full The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)
title_fullStr The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)
title_full_unstemmed The effect of graded methaemoglobin levels on the swimming performance in chinook salmon (Oncorhynchus tshawytscha)
title_sort effect of graded methaemoglobin levels on the swimming performance in chinook salmon (oncorhynchus tshawytscha)
publisher Inglaterra
publishDate 2020
url https://repositorio.inpa.gov.br/handle/1/23332
_version_ 1787143022026162176
score 11.755432

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