Hepatic triglyceride lipase in diabetic dogs

Abstract

Listen

Translate article

Circulating triglyceride is cleared by a combination of hepatic triglyceride lipase (H-TGL) and lipoprotein lipase (LPL). Although LPL has been extensively studied in diabetes, the effect of insulinization on H-TGL activity has not been well characterized. To determine whether H-TGL activity is altered in insulin-deficient diabetes, postheparin plasma was obtained from eight beagle dogs: three normal (nondiabetic) control dogs and five pancreatectomized diabetic dogs were studied acutely in poor diabetic control (underinsulinized), and again in short-term good control (well insulinized). Plasma glucose, measured at the start of the studies, was 88 ± 10 mg 100 mL (mean ± SD) in the normal control dogs, 434 ± 31 mL in pancreatectomized dogs in poor diabetic control, and 87 ± 16 in good diabetic control. Peak (five minutes) postheparin plasma H-TGL activity was increased in dogs in poor diabetic control (212 ± 43 nmol FFA/min/mL) v the normal control dogs (135 ± 21 nmol FFA/min/mL, P < 0.02). When the dogs were in good diabetic control, the peak H-TGL (202 ± 40 nmol FFA/min/mL) was also significantly increased compared with the level in normal dogs, while the sum of five and 45 minute postheparin H-TGL levels for the dogs in good diabetic control was less than when they were in poor diabetic control ( P < 0.01). Thus, insulin-deficient diabetes in dogs increases H-TGL, and short-term improvement of glycemic control with insulin partially corrects this increase.