Temperature and respiratory function in ectothermic vertebrates

Autor(es)

da Silva, Glauber S. F. ^[1] ; Glass, Mogens L. ^[2] ; Branco, Luiz G. S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Morphol Physiol & Pathol, FORP, Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Dept Physiol, FMRP, Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo de Revisão
• Fonte: Journal of Thermal Biology; v. 38, n. 2, p. 55-63, FEB 2013.
• Citações Web of Science: 13

Resumo

Pulmonary ventilation is adjusted to maintain balance between O-2 demands and CO2 elimination, which is essential for acid-base status in land ectothermic vertebrates. Rising temperatures cause increases in O-2 consumption (Q(10) effect) and decreases in the O-2 affinity of hemoglobin (a rightward shift in the oxygen-hemoglobin dissociation curve). These changes in air-breathing ectotherms are not proportional, i.e., the increased ventilation is relatively smaller than the change in metabolic rate. Therefore, the ratio between ventilation and metabolic rate is reduced, and consequently blood pH changes inversely with temperature. The combination of high temperatures and hypoxia exposure results in an amplified increase of ventilation, which may be explained by the balance between increased O-2-demand and decreased O-2-supply as well as increased O-2-chemoreceptors sensitivity. High temperature also increases pulmonary diffusing capacity. Global warming is expected to have significant impacts on the world's climate, with temperature changes affecting living organisms, in relation to their physiology and distribution. These physiological mechanisms and their capacity to respond appropriately to temperature illustrate the complexity of the relationship between ambient temperature and the respiratory function in ectothermic vertebrates, which are particularly susceptible to change in their environment. (c) 2012 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 07/58547-4 - Regulação ácido-base em relação a temperatura: pesquisando o modelo de Alphastat (Reeves, 1972)
• Beneficiário: Mogens Lesner Glass
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 06/60696-5 - Papel do núcleo obscuro da rafe na quimiossensibilidade ao CO2/pH
• Beneficiário: Glauber dos Santos Ferreira da Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 09/53916-7 - Avaliação dos padrões do mecanismo de ventilação pulmonar em Lepidosiren paradoxa (Dipnoi), comparado ao modelo jet stream (de Jongh e GaN, 1969), através das equações do espaço morto
• Beneficiário: Mogens Lesner Glass
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 10/52466-5 - Efeito do sulfeto de hidrogênio (H2S) na resposta ventilatória a hipercapnia
• Beneficiário: Glauber dos Santos Ferreira da Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado