Adaptations of the hemoglobinless Antarctic icefish (Channichthyidae) to hypoxia tolerance

Abstract

Antarctic fish of the family Channichthyidae, or icefish, represent a unique model for the study of physiological and biochemical responses to chronic hypoxia since the genes coding for hemoglobin and possible myoglobin are not expressed by these teleosts. Channichthyidae have developed outstanding cardio-vascular adaptations to accommodate the lack of these hemic pigments, most of them involving the myocardium.