Interaction of size-fractionated heparins with lipoprotein lipase and hepatic lipase in the rat

Heparin and heparin partially depolymerized by enzymic digestion were separated into six size fractions. Hep 1 (tetrasaccharides), with a mean M(r) of 1200, did not release significant amounts of either lipoprotein lipase (LPL) or hepatic lipase (HL) on intravenous injection into rats. Hep 2 (mainly octa- and deca-saccharides), with a mean M(r) of 2400-3000, released both lipases. To evoke the same plasma activity of LPL and HL required about 10 times more by weight, or about 40 times more molecules, of this heparin than of hep 5 (mean M(r) 12,000, similar to conventional heparin). Hep 5 impeded binding and degradation of 125I-labelled bovine LPL by perfused rat livers. In contrast, hep 2 had no detectable effect on these processes. This demonstrates a difference between the sites in the liver that mediate binding, uptake and degradation of LPL, and the extrahepatic sites that bind functional LPL, and the hepatic sites that bind functional HL. After injection of 3.25 mg of hep 5/kg body weight, plasma LPL activity rapidly rose and then remained high for at least 1 h. With hep 2, plasma LPL also rose rapidly, but then decreased to almost basal by 1 h. When a labelled triacylglycerol emulsion was injected 1 h after the heparins, the fractional catabolic rate was enhanced in the rats that had received conventional heparin, as expected from the high plasma LPL activity, but decreased compared with controls in rats that had received hep 2, indicating that available LPL had been depleted through enhanced transport to and uptake in the liver.

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Oral Estrogen Replacement Therapy in Postmenopausal Women Selectively Raises Levels and Production Rates of Lipoprotein A-I and Lowers Hepatic Lipase Activity Without Lowering the Fractional Catabolic Rate

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/01.atv.16.3.431 ◽

1996 ◽

Vol 16 (3) ◽

pp. 431-440 ◽

Cited By ~ 74

Author(s):

Eliot A. Brinton

Keyword(s):

Replacement Therapy ◽

Postmenopausal Women ◽

Lipase Activity ◽

Estrogen Replacement Therapy ◽

Hepatic Lipase ◽

Fractional Catabolic Rate ◽

Estrogen Replacement ◽

Hepatic Lipase Activity ◽

Oral Estrogen ◽

Catabolic Rate

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Some Factors Influencing Metabolism and Distribution of Fibrinogen in Man and Rabbits

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649225 ◽

1977 ◽

Vol 37 (02) ◽

pp. 243-252

Author(s):

Yi-Hsiang Chen ◽

E. B Reeve

Keyword(s):

Plasma Fibrinogen ◽

Synthesis Rate ◽

Fibrinogen Concentration ◽

Fractional Catabolic Rate ◽

System Parameters ◽

Catabolic Rate ◽

Simultaneous Decrease ◽

Normal Males ◽

Healthy Females ◽

Made In

SummaryTo shed some light on the homeostatic regulation of plasma fibrinogen, metabolic studies were made in healthy females, and in normal, thyroidectomized, and thyroxine-treated rabbits. In females, compared with normal males, plasma fibrinogen concentration, plasma and interstitial fibrinogen decreased consequent to an increased fractional catabolic rate and a normal fibrinogen synthesis rate. The interstitial/plasma fibrinogen ratio remained unchanged. In normal rabbits, with increasing body weight fractional catabolic rate and catabolic rate decreased, while fibrinogen concentration and plasma fibrinogen remained constant owing to a simultaneous decrease in fibrinogen synthesis. In addition, fractional transcapillary transfer rate and transcapillary flux also decreased resulting in a shrinkage of interstitial fibrinogen. Thyroidectomy and thyroxine-injection markedly altered fibrinogen metabolism: thyroid hormone accelerated fibrinogen catabolism but also stimulated synthesis. The net result was an increase in plasma fibrinogen and fibrinogen concentration. The interstitial/plasma fibrinogen ratio decreased in thyroxine-treated, and increased in thyroidectomized animals. This study defines the variations of the fibrinogen system parameters in these physiologic and pathologic conditions, and illustrates some patterns of alterations in fibrinogen metabolism.

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The Effect of Adrenaline Infusions on Blood Coagulation in Normal and Haemophilia B Dogs

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649437 ◽

1966 ◽

Vol 15 (03/04) ◽

pp. 349-364 ◽

Cited By ~ 5

Author(s):

A.H Özge ◽

H.C Rowsell ◽

H.G Downie ◽

J.F Mustard

Keyword(s):

Body Weight ◽

Factor Viii ◽

Factor Ix ◽

Clotting Factor ◽

Blood Ph ◽

Order Of Magnitude ◽

Dose Dependent ◽

Generation Test ◽

Plasma Activity

SummaryThe addition of trace amounts of adrenaline to whole blood in plasma in vitro increased factor VIII, factor IX and whole plasma activity in the thromboplastin generation test. This was dose dependent.Adrenaline infusions less than 22 (μg/kg body weight in normal dogs accelerated clotting, increased factor IX, factor VIII and whole plasma activity in the thromboplastin generation test and caused a fall in blood pH. In a factor IX deficient dog, there was no increase in factor IX activity. After adrenaline infusions, however, the other changes occurred and were of the same order of magnitude as in the normal. Adrenaline in doses greater than 22 μg/kg body weight did not produce as great an effect on clotting in normal or factor IX deficient dogs. The platelet count in the peripheral blood was increased following the infusion of all doses of adrenaline. These observations suggest that the accelerating effect of adrenaline on clotting is not mediated through increase in activity of a specific clotting factor.

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Catabolism of Human Fibrinogen Fragment D in Normal Subjects and Patients with Liver Cirrhosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650106 ◽

1980 ◽

Vol 44 (03) ◽

pp. 146-149 ◽

Cited By ~ 3

Author(s):

Nicole Ardaillou ◽

Jeannine Yvart ◽

Philippe Le Bras ◽

Marie-José Larrieu

Keyword(s):

Liver Cirrhosis ◽

Clearance Rate ◽

Plasma Clearance ◽

Normal Subjects ◽

Fractional Catabolic Rate ◽

Human Fibrinogen ◽

Plasma Pool ◽

Catabolic Rate ◽

Chloramine T

SummaryThe catabolism of human fragment D, (FgD), obtained by plasmin digestion of fibrinogen has been investigated in normal subjects and patients with liver cirrhosis and the results compared with those obtained for fibrinogen (Fg). Fg was labelled with I-125 and Fg D with I-131 using the chloramine T method. The plasma disappearance curves of both labelled proteins fitted a two exponential curve. In controls the plasma clearance rate of Fg D was greater than that of Fg as shown by the marked difference between the half-lives of these two tracers: 8,9 and 83,5 hours for Fg D and Fg respectively. The fractional catabolic rate of Fg D was 3.38 times the plasma pool per day. In nine patients with liver cirrhosis, catabolism of Fg was not modified. In contrast, catabolism of Fg D was significantly reduced with a half life of 13.0 hours and a low fractional catabolic rate. These results suggest the role of the liver in the catabolism of Fg D in man.

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Differential effect of combined lipase deficiency (cld/cld) on human hepatic lipase and lipoprotein lipase secretion

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)31512-1 ◽

2001 ◽

Vol 42 (11) ◽

pp. 1858-1864 ◽

Cited By ~ 3

Author(s):

Jennifer C. Boedeker ◽

Mark H. Doolittle ◽

Ann L. White

Keyword(s):

Lipoprotein Lipase ◽

Differential Effect ◽

Hepatic Lipase

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Metabolism of chylomicron phosphatidylinositol in the rat: fate in vivo and hydrolysis with lipoprotein lipase and hepatic lipase in vitro.

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)39921-1 ◽

1994 ◽

Vol 35 (12) ◽

pp. 2151-2160

Author(s):

A Nilsson ◽

Q Chen ◽

E Dahlman

Keyword(s):

Lipoprotein Lipase ◽

Hepatic Lipase

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Increased Apolipoprotein AI Production Rate and Redistribution of High-Density Lipoprotein Size Induced by Estrogen plus Progestin as Oral Contraceptive

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2009-1402 ◽

2009 ◽

Vol 94 (12) ◽

pp. 4891-4897 ◽

Cited By ~ 7

Author(s):

Laurence Duvillard ◽

Guillaume Dautin ◽

Emmanuel Florentin ◽

Aline Jeannin ◽

Jean-Paul Pais de Barros ◽

...

Keyword(s):

Oral Contraceptive ◽

High Density Lipoprotein ◽

Production Rate ◽

Density Lipoprotein ◽

High Density ◽

Pool Size ◽

Fractional Catabolic Rate ◽

Fed State ◽

Catabolic Rate ◽

Estrogen Plus Progestin

Context: The impact of estrogen plus progestin as an oral contraceptive on high density lipoprotein (HDL) apolipoprotein (apo) AI metabolism in humans is poorly understood. Objectives: This study was designed to measure the in vivo effect of Moneva (30 μg ethinylestradiol, 75 μg gestodene) on HDL apoAI production rate and fractional catabolic rate. Design: Using 13C-leucine, we performed two kinetic studies in the fed state in 10 normolipidemic young women, before and 3 months after beginning Moneva. Results: On Moneva, serum triglycerides increased by 12% (P = 0.03) in the fed state, whereas low-density lipoprotein and HDL cholesterol remained unchanged. HDL apoAI pool size and production rate were increased by 9.2% (67.3 ± 7.1 vs. 61.6 ± 6.7 mg · kg−1; P = 0.05) and 26.5% (14.3 ± 2.7 vs. 11.3 ± 2.2 mg · kg−1 · d−1; P = 0.02), respectively. HDL apoAI fractional catabolic rate was not significantly modified. Three-month treatment by Moneva induced a shift of HDL size distribution from HDL2 toward HDL3 (HDL3 = 51.5 ± 8.1 vs. 46.5 ± 9.2% of total HDL; P = 0.02) and an increase in the proportion of apoAI among HDL components (38.8 ± 4.3 vs. 34.4 ± 2.8%; P = 0.01). Conclusion: Oral contraception by estrogen plus progestin induces changes in HDL apoAI metabolism characterized by an increase in production rate and pool size, with a higher proportion of HDL3 particles. Whether or not these changes are beneficial to prevent atherosclerosis has to be explored further.

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