Regional glycerol and free fatty acid metabolism before and after meal ingestion

MD Jensen - American Journal of Physiology …, 1999 - journals.physiology.org
MD Jensen
American Journal of Physiology-Endocrinology and Metabolism, 1999journals.physiology.org
We measured splanchnic and leg glycerol [and free fatty acid (FFA)] uptake and release in
11 healthy volunteers before and after meal ingestion to assess whether regional FFA-to-
glycerol release ratios mirror systemic release ratios. Basal splanchnic triglyceride release
was also assessed. Although basal splanchnic glycerol uptake (111±18 μmol/min)
accounted for most of systemic glycerol rate of appearance (156±20 μmol/min), leg glycerol
uptake was also noted. The basal, systemic FFA-to-glycerol release ratio was less (2.6±0.2 …
We measured splanchnic and leg glycerol [and free fatty acid (FFA)] uptake and release in 11 healthy volunteers before and after meal ingestion to assess whether regional FFA-to-glycerol release ratios mirror systemic release ratios. Basal splanchnic triglyceride release was also assessed. Although basal splanchnic glycerol uptake (111 ± 18 μmol/min) accounted for most of systemic glycerol rate of appearance (156 ± 20 μmol/min), leg glycerol uptake was also noted. The basal, systemic FFA-to-glycerol release ratio was less (2.6 ± 0.2,P < 0.05) than the splanchnic ratio of 6.1 ± 1.3, and the leg FFA-to-glycerol release ratio under fed conditions was less than the systemic ratio (0.9 ± 0.1 vs. 1.6 ± 0.2, respectively, P< 0.05). Basal splanchnic triglyceride production rates were 74 ± 20 μmol/min, which could produce equimolar amounts of glycerol in the peripheral circulation via lipoprotein lipase action. In summary, 1) regional FFA-to-glycerol release ratios do not mirror systemic ratios,2) leg glycerol uptake occurs in humans, and 3) splanchnic triglyceride production rates are substantial relative to systemic glycerol appearance. Glycerol appearance rates may not be a quantitative index of whole body lipolysis.
American Physiological Society