Secretion and contribution to lipolysis of gastric and pancreatic lipases during a test meal in humans.
BACKGROUND
The aim of this study was to quantitatively evaluate the relative contributions to in vivo lipolysis of gastric and pancreatic lipases.


METHODS
Gastric and pancreatic lipase secretions were measured, and their respective levels were determined in duodenal fluid during the digestion of a liquid test meal in healthy volunteers. Gastric lipase activity was clearly distinguished from that of pancreatic lipase by using both a specific enzymatic assay and an enzyme-linked immunosorbent assay. Lipolysis products were monitored throughout the digestion period.


RESULTS
On a weight basis, the ratio of pancreatic lipase to gastric lipase total secretory outputs was found to be around four after 3 hours of digestion. The level of gastric hydrolysis was calculated to be 10% +/- 1% of the acyl chains released from the meal triglycerides. Gastric lipase remained active in the duodenum where it might still hydrolyze 7.5% of the triglyceride acyl chains.


CONCLUSIONS
Globally during the whole digestion period, gastric lipase might hydrolyze 17.5% of the triglyceride acyl chains. In other words, gastric lipase might hydrolyze 1 acyl chain of 4, which need to be hydrolyzed for a complete intestinal absorption of monoglycerides and free fatty acids resulting from the degradation of two triglyceride molecules.
Carriere
F
F
Laboratoire de Lipolyse Enzymatique, Centre National de la Recherche Scientifique, Marseille, France.
Barrowman
J A
JA
Verger
R
R
Laugier
R
R
D000328:Adult; D004386:Duodenum / Q000737:chemistry / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005227:Fatty Acids / Q000378:metabolism; D005502:Food; D005746:Gastric Emptying / Q000502:physiology; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007408:Intestinal Absorption / Q000502:physiology; D008049:Lipase / Q000378:metabolism* / Q000502:physiology*; D008066:Lipolysis / Q000502:physiology*; D010179:Pancreas / Q000201:enzymology*; D013270:Stomach / Q000737:chemistry / Q000201:enzymology*; D014280:Triglycerides / Q000378:metabolism
D005227:Fatty Acids; D014280:Triglycerides; D008049:Lipase