Vascular Adaptations for a Low Pressure / High Flow
Blood Supply to Locomotory Muscles of Antarctic
Icefish
Stuart Egginton i and J.CliffRankin 2
iDepartment of Physiology, University of Birmingham, UK
2Institute of Biology, Odense University, Denmark
Introduction
The extremely stable Antarctic environment may be expected to have
produced a number of cardiovascular adaptations to offset increased blood
viscosity and/or decreased oxygen diffusion rates in the cold [1,2]. The
ichthyofauna is dominated by Notothenioids which have a modest
haematocrit and a reduced blood haemoglobin concentration [3], a
situation taken to the extreme in the icefish (channichthyids) that possess
only a few vestigial erythrocytes and no respiratory pigment. Low blood
pressure and large venous return reported for icefish [4] would best be
accommodated by a relatively low afterload on the heart [5]. Evidence for
the origin of the assumed low peripheral resistance in icefish was sought
in the morphology of the blood vascular system; preliminary results from
this study were reported as abstracts [6,7].
Material and Methods
Fish used for vascular casting were caught by bottom or benthopelagic
trawling at 360 - 600 m depth from the RV "Polarstern" in the Weddell
Sea (71-75°S, 13-28°W) on the ANTARKTIS VIII4 (EPOS) expedition in
1989. Seventeen individuals of 6 species of the family Channichthyidae
(icefish) were used for vascular casting with Acrifix (A) plus 27
individuals of 8 species with Microfil (M) as follows: Chaenocephalus
aceratus Lannberg (A, M); Cryodraco antarcticus Dollo (M);
Chionodraco myersi DeWitt and Tyler (A, M); Chionodraco hamatus
Lannberg (A, M); Chionodraco rastrospinosus DeWitt and Hureau (A,
M); Champsocepha/us gunnari Lannberg CA, M); Pseudochaenichthys
georgianus Norman (A, M); Chionobathyscus dewitti Andriashev and
Neelov; Neopagetopsis ionah Nybelin (M). In addition, Microfil casts
G. di Prisco, E. Pisano, A. Clarke (Eds)
Fishes of Antarctica. A biological overview
© Springer-Verlag Italia 1998
Blood Supply to Locomotory Muscles of Antarctic
Icefish
Stuart Egginton i and J.CliffRankin 2
iDepartment of Physiology, University of Birmingham, UK
2Institute of Biology, Odense University, Denmark
Introduction
The extremely stable Antarctic environment may be expected to have
produced a number of cardiovascular adaptations to offset increased blood
viscosity and/or decreased oxygen diffusion rates in the cold [1,2]. The
ichthyofauna is dominated by Notothenioids which have a modest
haematocrit and a reduced blood haemoglobin concentration [3], a
situation taken to the extreme in the icefish (channichthyids) that possess
only a few vestigial erythrocytes and no respiratory pigment. Low blood
pressure and large venous return reported for icefish [4] would best be
accommodated by a relatively low afterload on the heart [5]. Evidence for
the origin of the assumed low peripheral resistance in icefish was sought
in the morphology of the blood vascular system; preliminary results from
this study were reported as abstracts [6,7].
Material and Methods
Fish used for vascular casting were caught by bottom or benthopelagic
trawling at 360 - 600 m depth from the RV "Polarstern" in the Weddell
Sea (71-75°S, 13-28°W) on the ANTARKTIS VIII4 (EPOS) expedition in
1989. Seventeen individuals of 6 species of the family Channichthyidae
(icefish) were used for vascular casting with Acrifix (A) plus 27
individuals of 8 species with Microfil (M) as follows: Chaenocephalus
aceratus Lannberg (A, M); Cryodraco antarcticus Dollo (M);
Chionodraco myersi DeWitt and Tyler (A, M); Chionodraco hamatus
Lannberg (A, M); Chionodraco rastrospinosus DeWitt and Hureau (A,
M); Champsocepha/us gunnari Lannberg CA, M); Pseudochaenichthys
georgianus Norman (A, M); Chionobathyscus dewitti Andriashev and
Neelov; Neopagetopsis ionah Nybelin (M). In addition, Microfil casts
G. di Prisco, E. Pisano, A. Clarke (Eds)
Fishes of Antarctica. A biological overview
© Springer-Verlag Italia 1998