Changes of the endogenous lipoprotein lipase activity during oral glucose tolerance test.

Since Hahn’s observation of the postalimentary lipemia clearing actIvity following the injection of heparin, physiological, biochemical and clinical significances of the postheparin lipoprotein lipase have been well clarified. The presence of the endogenous lipoprotein lipase in human blood, which was at first doubted, has been repeatedly confirmed2∼8. Recent papers9,10 described elevated endogenous lipoprotein lipase activity in patients with essential hyperlipemia after ample fat uptake. In this preliminary report, changes of the lipoprotein lipase activity during oral glucose tolerance test is illustrated. ∗PMID: 4230850 [PubMed indexed for MEDLINE] Copyright c ©OKAYAMA UNIVERSITY MEDICAL SCHOOL Acta Moo. Okayama 21, 185-189 (1967) BRIEF NOTES CHANGES OF THE ENDOGENOUS LIPOPROTEIN LIPASE ACTIVITY DURING ORAL GLUCOSE TOLERANCE TEST Koichi KAWANI SRI Department of Internal Medicine, Okayama University Medical School, Okayama, Japan (Director: Prof. K. Hiraki) Received for publication, July 26, 1967 Since Hahn's observation of the postalimentary lipemia clearing actIvity following the injection of heparin, physiological, biochemical and clinical significances of the postheparin lipoprotein lipase have been well clarified. The presence of the endogenous lipoprotein lipase in human blood, which was at first doubted, has been repeatedly confirmeds• Recent papers. 10 described elevated endogenous lipoprotein lipase activity in patients with essential hyperlipemia after ample fat uptake. In this preliminary report, changes of the lipoprotein lipase activity during oral glucose tolerance test is illustrated. Measurement of the lipoprotein lipase (LPL) activity was performed by determination of the release of free fatty acid (FFA) in vitro • In normal persons (10 cases) (Fig. 1), no LPL activity was demonstrated in the plasma before and 30, 120 and 180 minutes after glucose intake. And, elevated LPL activity was observed at 60 and 90, and 150 minutes after glucose intake, showing two peaks of the LPL activity. After incubation (at 37°C for half an hour) of the plasma mixed with sesame oil (Fatgen), the identical changes of the LPL activity curve were observed. But the peaks of the enzymatic activity of the postincubation plasma were about three times as high as that of the prcin~ ubation plasma. In diabetics (9 cases) (Fig. 2), the LPL activity in plasma before incubation was quite different from changes in normal persons. No activity was observed before glucose intake, but the activity in the plasma rose at 30, 60 and 90 minutes, when the activity reached a peak, and then the activity decreased 120, 150 and 180 minutes after glucose intake, finally showing almost no activity. The elevation of the enzymatic activity in diabetics was higher than that in normal persons. After incubation of the plasma mixed with sesame oil (Fatgen), identical changes of the LPL activity curve were also observed, demonstrating 185 1 Kawanishi: Changes of the endogenous lipoprotein lipase activity during oral Produced by The Berkeley Electronic Press, 1967