Effect of starvation and insulin in vivo on the activity of the pyruvate dehydrogenase complex in rat skeletal muscles.
The in vivo responses of pyruvate dehydrogenase (PDH) complex to starvation and insulin was assessed in heart, diaphragm and red quadriceps muscle. PDH complex activity was decreased by starvation (3.4-10.2-fold), the magnitude of change depending on muscle type. Insulin increased PDH activity in all muscle types. In fed rats, this effect was relatively small (1.25-1.29-fold). In starved rats there were effects in heart (4.3-fold) and red quadriceps (1.7-fold) but no effect in diaphragm. These results demonstrate that PDH complex in different groups of muscle has different insulin sensitivity (particularly in tissues from starved animals).
Denyer
G S
GS
Department of Endocrinology, Royal Prince Alfred Hospital, Sydney, Australia.
Lam
D
D
Cooney
G J
GJ
Caterson
I D
ID
D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000201:enzymology; D000818:Animals; D002950:Citrate (si)-Synthase / Q000378:metabolism; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D008931:Mitochondria, Muscle / Q000187:drug effects* / Q000201:enzymology; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013217:Starvation
D007328:Insulin; D011768:Pyruvate Dehydrogenase Complex; D002950:Citrate (si)-Synthase