Metabolic state of the in situ perfused trout heart during severe hypoxia

P. G. Arthur, J. E. Keen, P. W. Hochachka, A. P. Farrell

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

An in situ perfused heart preparation was used to study the effects of severe hypoxia in the rainbow trout, Oncorhynchus mykiss. Hypoxic trout hearts were capable of generating similar power outputs and ATP turnovers to normoxic counterparts at subphysiological work regimes. However, lactate efflux was 35-fold higher and glycolytic rate was calculated to be >10-fold higher in hypoxic than in normoxic hearts. The surprising ability of trout hearts to withstand severe hypoxia appears to be related to the rapid removal of lactate and associated protons from the heart. An increase in power demand to normal in vivo levels caused rapid failure in hypoxic hearts. Failure was caused by a decline in stroke volume (contractility) and was not a consequence of heart rate deterioration. Hypoxia caused marked declines in the concentration of creatine phosphate but not ATP, and we suggest that an increase in intracellular phosphate was the primary cause of failure.

Original languageEnglish
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume263
Issue number4 32-4
Publication statusPublished - 1992
Externally publishedYes

Fingerprint Dive into the research topics of 'Metabolic state of the in situ perfused trout heart during severe hypoxia'. Together they form a unique fingerprint.

Cite this