TY - JOUR
T1 - Metabolic depression during aestivation does not involve remodelling of membrane fatty acids in two Australian frogs
AU - Berner, Nancy J.
AU - Else, P. L.
AU - Hulbert, A. J.
AU - Mantle, B. L.
AU - Cramp, R. L.
AU - Franklin, C. E.
N1 - Funding Information:
Acknowledgments We would like to thank Robyn Godfrey and Ben Jing Wu for help in some of the measurements on C. australis. This research was funded by the Andrew W. Mellon Foundation Trust through the Appalachian College Association and Faculty Research Funds from the University of the South to N. J. Berner and grants through the Australian Research Council to A. J. Hulbert, P. Else and C. E. Franklin.
PY - 2009/9
Y1 - 2009/9
N2 - Changes in membrane lipid composition (membrane remodelling) have been associated with metabolic depression in some aestivating snails but has not been studied in aestivating frogs. This study examined the membrane phospholipid composition of two Australian aestivating frog species Cyclorana alboguttata and Cyclorana australis. The results showed no major membrane remodelling of tissue in either frog species, or in mitochondria of C. alboguttata due to aestivation. Mitochondrial membrane remodelling was not investigated in C. australis. Where investigated in C. alboguttata, total protein and phospholipid content, and citrate synthase (CS) and cytochrome c oxidase (CCO) activities in tissues and mitochondria mostly did not change with aestivation in liver. In skeletal muscle, however, CS and CCO activities, mitochondrial and tissue phospholipids, and mitochondrial protein decreased with aestivation. These decreases in muscle indicate that skeletal muscle mitochondrial content may decrease during aestivation. Na+K+ATPase activity of both frog species showed no effect of aestivation. In C. alboguttata different fat diets had a major effect on both tissue and mitochondrial phospholipid composition indicating an ability to remodel membrane composition that is not utilised in aestivation. Therefore, changes in lipid composition associated with some aestivating snails do not occur during aestivation in these Australian frogs.
AB - Changes in membrane lipid composition (membrane remodelling) have been associated with metabolic depression in some aestivating snails but has not been studied in aestivating frogs. This study examined the membrane phospholipid composition of two Australian aestivating frog species Cyclorana alboguttata and Cyclorana australis. The results showed no major membrane remodelling of tissue in either frog species, or in mitochondria of C. alboguttata due to aestivation. Mitochondrial membrane remodelling was not investigated in C. australis. Where investigated in C. alboguttata, total protein and phospholipid content, and citrate synthase (CS) and cytochrome c oxidase (CCO) activities in tissues and mitochondria mostly did not change with aestivation in liver. In skeletal muscle, however, CS and CCO activities, mitochondrial and tissue phospholipids, and mitochondrial protein decreased with aestivation. These decreases in muscle indicate that skeletal muscle mitochondrial content may decrease during aestivation. Na+K+ATPase activity of both frog species showed no effect of aestivation. In C. alboguttata different fat diets had a major effect on both tissue and mitochondrial phospholipid composition indicating an ability to remodel membrane composition that is not utilised in aestivation. Therefore, changes in lipid composition associated with some aestivating snails do not occur during aestivation in these Australian frogs.
KW - Citrate synthase
KW - Cytochrome c oxidase
KW - Fatty acid composition
KW - Membrane remodelling
KW - Metabolic depression
KW - NaKATPase
UR - http://www.scopus.com/inward/record.url?scp=70350164127&partnerID=8YFLogxK
U2 - 10.1007/s00360-009-0368-y
DO - 10.1007/s00360-009-0368-y
M3 - Article
C2 - 19466430
AN - SCOPUS:70350164127
SN - 0174-1578
VL - 179
SP - 857
EP - 866
JO - Journal of Comparative Physiology B: biochemical, systemic, and environmental physiology
JF - Journal of Comparative Physiology B: biochemical, systemic, and environmental physiology
IS - 7
ER -