Effects of diabetes and insulin on ketone bodies metabolism in heart.
This work investigates the effect of alloxan-induced short-term diabetes (24 h) on D-3-hydroxybutyrate metabolism at physiological and non-physiological concentrations of the ketone body in the isolated non-working perfused rat heart. Also the effect of insulin (2 mU.ml-1) on D-3-hydroxybutyrate metabolism was investigated in hearts from normal and diabetic rats. The rates of D-3-hydroxybutyrate utilization and oxidation and of acetoacetate production were proportional to D-3-hydroxybutyrate concentration. The utilization of D-3-hydroxybutyrate showed saturation kinetics in hearts from normal and diabetic rats, in the presence and absence of insulin. Acute short-term diabetes augmented D-3-hydroxybutyrate utilization and oxidation at 1.25 and 2.5 mM DL-3-HB, with no significant effect at higher concentrations, but increased acetoacetate production at all investigated concentrations. In hearts from normal rats, insulin enhanced D-3-hydroxybutyrate utilization and oxidation at 2.5, 5, and 10 mM DL-3-HB, but no effect was observed at the lowest (1.25 mM) and highest (16 mM) DL-3-HB concentrations. Insulin had no effect on D-3-hydroxybutyrate metabolism in hearts from diabetic rats. No significant effect of insulin on the rate of acetoacetate production in normal and diabetic states was observed.
Sultan
A M
AM
Department of Medical Sciences Umm Al-Qura University Makkah, Saudi Arabia.
D020155:3-Hydroxybutyric Acid; D000090:Acetoacetates / Q000378:metabolism; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D006885:Hydroxybutyrates / Q000378:metabolism; D007328:Insulin / Q000502:physiology*; D007657:Ketone Bodies / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D000090:Acetoacetates; D006885:Hydroxybutyrates; D007328:Insulin; D007657:Ketone Bodies; C016635:acetoacetic acid; D020155:3-Hydroxybutyric Acid