PMID- 18593602
OWN - NLM
STAT- MEDLINE
DCOM- 20080915
LR  - 20131121
IS  - 1531-4332 (Electronic)
IS  - 1095-6433 (Linking)
VI  - 151
IP  - 1
DP  - 2008 Sep
TI  - Carbohydrate and amino acid metabolism in fasting and aestivating African 
      lungfish (Protopterus dolloi).
PG  - 85-92
LID - 10.1016/j.cbpa.2008.06.003 [doi]
AB  - The potential importance of carbohydrates and amino acids as fuels during periods 
      of fasting and aestivation in the African lungfish, Protopterus dolloi, were 
      examined. No significant decreases in tissue glycogen levels were observed 
      following 60 days of fasting or aestivation, suggesting lungfish may undergo 
      'glycogen sparing'. Yet glycogenolysis may be important during aestivation based 
      on the differing responses of two flux-generating enzymes of the glycolytic 
      pathway, hexokinase (HK) and pyruvate kinase (PK). PK is required for glycogen 
      breakdown whereas HK is not. HK activity is significantly down-regulated in the 
      heart and gill tissues during aestivation, while PK activity is sustained. The 
      significant negative correlation between the activity of HK and glucose levels in 
      the heart of aestivating lungfish suggests HK may be regulated by glucose 
      concentrations. There was no indication of anaerobic glycolytic flux during 
      aestivation as lactate did not accumulate in any of the tissues examined, and no 
      significant induction of lactate dehydrogenase (LDH)activity was observed. The 
      increase in glutamate dehydrogenase (GDH) and aspartate aminotransferase (Asp-AT) 
      activities in the liver of aestivating P. dolloi suggests some energy may be 
      obtained via increased aminoacid catabolism, leading to the generation of 
      tricarboxylic acid (TCA) cycle intermediates. These findings indicate the 
      importance of both carbohydrate and amino acid fuel stores during aestivation in 
      aphylogenetically ancient, air-breathing fish.
FAU - Frick, Natasha Therese
AU  - Frick NT
AD  - Department of Integrative Biology, University of Guelph, Guelph, Ont. N1G2W1, 
      Canada.
FAU - Bystriansky, Jason Scott
AU  - Bystriansky JS
FAU - Ip, Yuen Kwong
AU  - Ip YK
FAU - Chew, Shit Fun
AU  - Chew SF
FAU - Ballantyne, James Stuart
AU  - Ballantyne JS
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20080614
PL  - United States
TA  - Comp Biochem Physiol A Mol Integr Physiol
JT  - Comparative biochemistry and physiology. Part A, Molecular & integrative 
      physiology
JID - 9806096
RN  - 0 (Amino Acids)
RN  - 0 (Blood Glucose)
RN  - 059QF0KO0R (Water)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 9005-79-2 (Glycogen)
RN  - EC 1.1.1.27 (L-Lactate Dehydrogenase)
RN  - EC 2.3.3.1 (Citrate (si)-Synthase)
RN  - EC 2.7.1.1 (Hexokinase)
SB  - IM
MH  - Africa
MH  - Amino Acids/*metabolism
MH  - Animals
MH  - Blood Glucose/metabolism
MH  - *Carbohydrate Metabolism
MH  - Citrate (si)-Synthase/metabolism
MH  - Estivation/*physiology
MH  - Fasting/*physiology
MH  - Fishes/*physiology
MH  - Gluconeogenesis
MH  - Glycogen/blood
MH  - Hexokinase/metabolism
MH  - L-Lactate Dehydrogenase/metabolism
MH  - Lactic Acid/blood
MH  - Muscles/metabolism
MH  - Myocardium/enzymology
MH  - Osmolar Concentration
MH  - Water/metabolism
EDAT- 2008/07/03 09:00
MHDA- 2008/09/16 09:00
CRDT- 2008/07/03 09:00
PHST- 2008/01/29 00:00 [received]
PHST- 2008/06/03 00:00 [revised]
PHST- 2008/06/04 00:00 [accepted]
PHST- 2008/07/03 09:00 [pubmed]
PHST- 2008/09/16 09:00 [medline]
PHST- 2008/07/03 09:00 [entrez]
AID - S1095-6433(08)00992-6 [pii]
AID - 10.1016/j.cbpa.2008.06.003 [doi]
PST - ppublish
SO  - Comp Biochem Physiol A Mol Integr Physiol. 2008 Sep;151(1):85-92. doi: 
      10.1016/j.cbpa.2008.06.003. Epub 2008 Jun 14.