Control of muscle pyruvate oxidation during late pregnancy.
Despite significant increases in circulating concentrations of lipid fuels (triacylglycerol, non-esterified fatty acids (NEFA) and ketone bodies) in late-pregnant rats sampled in the fed (absorptive) state, cardiac and skeletal muscle active pyruvate dehydrogenase (PDHa) activities remained comparable with those observed in fed, age-matched virgin controls. Cardiac PDHa activity was suppressed in response to acute (6 h) starvation in late-pregnant (as well as virgin) rats: this inactivation was opposed by inhibition of mitochondrial long-chain FA oxidation. Starvation (6 h) also led to PDH inactivation in skeletal muscles of late-pregnant, but not virgin, rats. Starvation for 24 h led to further suppression of cardiac PDHa activity and was associated with significant increases in PDH kinase activities in both virgin and late-pregnant rats. Late pregnancy did not itself influence cardiac PDH kinase activity.
Sugden
M C
MC
Department of Biochemistry, Faculty of Basic Medical Sciences, Queen Mary & Westfield College, University of London, UK.
Holness
M J
MJ
D000818:Animals; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D007657:Ketone Bodies / Q000097:blood; D007773:Lactates / Q000097:blood; D008929:Mitochondria, Heart / Q000201:enzymology*; D008931:Mitochondria, Muscle / Q000201:enzymology*; D009132:Muscles / Q000378:metabolism*; D010084:Oxidation-Reduction; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism* / Q000502:physiology; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism*; D011773:Pyruvates / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D013217:Starvation; D014280:Triglycerides / Q000097:blood
D005230:Fatty Acids, Nonesterified; D007657:Ketone Bodies; D007773:Lactates; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D011768:Pyruvate Dehydrogenase Complex; D011773:Pyruvates; D014280:Triglycerides; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases