Synthesis and Secretion of Hepatic Lipase by Rat Hepatocytes

1987 ◽  
pp. 51-59
Author(s):  
Elizabeth A. Laposata ◽  
Jerome F. Strauss ◽  
Henry M. Laboda ◽  
Jane M. Glick
Keyword(s):  
Hepatic Lipase ◽  
Rat Hepatocytes

scholarly journals Hepatic lipase. Synthesis, processing, and secretion by isolated rat hepatocytes.

1987 ◽  
Vol 262 (11) ◽  
pp. 5333-5338 ◽  
Author(s):  
E.A. Laposata ◽  
H.M. Laboda ◽  
J.M. Glick ◽  
J.F. Strauss
Keyword(s):  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Isolated Rat Hepatocytes ◽  
Isolated Rat

Cell-Density-Dependent Release of Hepatic Lipase from Cultured Rat Hepatocytes

1989 ◽  
Vol 21 (01) ◽  
pp. 4-7 ◽  
Author(s):  
E. Jensen ◽  
P. Hansson ◽  
C.-H. Florén ◽  
Å Nilsson ◽  
P. Nilsson-Ehle
Keyword(s):  
Cell Density ◽  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Density Dependent ◽  
Cultured Rat Hepatocytes

Release of hepatic lipase and very low density lipoprotein by cultured rat hepatocytes

1986 ◽  
Vol 18 (10) ◽  
pp. 909-916 ◽  
Author(s):  
Arild C. Rustan ◽  
Jon Ø. Nossen ◽  
Jan P. Blomhoff ◽  
Christian A. Drevon
Keyword(s):  
Hepatic Lipase ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Rat Hepatocytes ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Cultured Rat Hepatocytes

Acute effects of adrenaline on hepatic lipase secretion by rat hepatocytes

Metabolism ◽  
1997 ◽  
Vol 46 (1) ◽  
pp. 76-82 ◽  
Author(s):  
Bernadette P. Neve ◽  
Adrie J.M. Verhoeven ◽  
Hans Jansen
Keyword(s):  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Acute Effects

scholarly journals Involvement of Leukotriene Production in Release of Hepatic Lipase Activity Produced by Heparin from Rat Hepatocytes

2006 ◽  
Vol 52 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Hisashi Tagashira ◽  
Rie Kerakawati ◽  
Toshio Motoyashiki ◽  
Tetsuo Morita
Keyword(s):  
Lipase Activity ◽  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Hepatic Lipase Activity

Acute regulation of hepatic lipase secretion by rat hepatocytes

2002 ◽  
Vol 80 (4) ◽  
pp. 467-474 ◽  
Author(s):  
Xavier Galan ◽  
Julia Peinado-Onsurbe ◽  
Monique Q Robert ◽  
Maria Soley ◽  
Miquel Llobera ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Opposite Effect ◽  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Acute Effect ◽  
Secreted Proteins ◽  
Similar Proportion ◽  
Epidermal Growth ◽  
Actin Mrna

Hepatic lipase is involved in cholesterol uptake by the liver. Although it is known that catecholamines are responsible for the daily variation of enzyme activity, the mechanisms involved are poorly understood. Rat hepatocytes incubated with adrenaline or other Ca2+-mobilizing hormones were used as an experimental model. Adrenaline reduced in a similar proportion the secretion of both hepatic lipase and albumin. The effect of adrenaline disappeared completely in cells exposed to cycloheximide. Adrenaline decreased incorporation of [35S]Met into cellular and secreted proteins, but it affected neither degradation of [35S]Met-prelabeled proteins nor the abundance of total and specific (albumin, hepatic lipase, beta-actin) mRNA. Other Ca2+-mobilizing agents had the opposite effect on hepatic lipase secretion: it was decreased by vasopressin but was increased by epidermal growth factor. Vasopressin and epidermal growth factor had the opposite effect on [35S]Met incorporation into cellular and secreted proteins, but neither affected hepatic lipase mRNA. The acute effect of adrenaline, vasopressin, and epidermal growth factor on hepatic lipase secretion is the consequence of the effect of these hormones on protein synthesis and is therefore nonspecific.Key words: adrenaline, vasopressin, epidermal growth factor, albumin secretion.

scholarly journals Involvement of Ca2+/Calmodulin-Dependent Protein Kinase II in Heparin-Stimulated Release of Hepatic Lipase Activity from Rat Hepatocytes

2005 ◽  
Vol 28 (3) ◽  
pp. 409-412 ◽  
Author(s):  
Hisashi Tagashira ◽  
Shinji Nakahigashi ◽  
Rie Kerakawati ◽  
Toshio Motoyashiki ◽  
Tetsuo Morita
Keyword(s):  
Protein Kinase ◽  
Lipase Activity ◽  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Dependent Protein Kinase ◽  
Hepatic Lipase Activity ◽  
Protein Kinase Ii ◽  
Dependent Protein

scholarly journals Hepatic lipase may act as a ligand in the uptake of artificial chylomicron remnant-like particles by isolated rat hepatocytes.

1994 ◽  
Vol 299 (3) ◽  
pp. 889-894 ◽  
Author(s):  
P Diard ◽  
M I Malewiak ◽  
D Lagrange ◽  
S Griglio
Keyword(s):  
Plasma Membranes ◽  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Lipolytic Enzyme ◽  
Chylomicron Remnant ◽  
Isolated Rat Hepatocytes ◽  
Isolated Rat

Active and heat-inactivated hepatic lipase stimulated to a statistically comparable extent the uptake of chylomicron remnant-like particles by isolated rat hepatocytes by 3-fold and 2.3-fold respectively and, likewise, their binding to hepatic plasma membranes by 5-fold and 4-fold respectively. Hepatic lipase may facilitate uptake of these particles, not only as a lipolytic enzyme, but also as a ligand anchored to extracellular glycosaminoglycans.

scholarly journals Maturation and secretion of rat hepatic lipase is inhibited by α1B-adrenergic stimulation through changes in Ca2+ homoeostasis: thapsigargin and EGTA both mimic the effect of adrenaline

1998 ◽  
Vol 330 (2) ◽  
pp. 701-706 ◽  
Author(s):  
P. Bernadette NEVE ◽  
J. M. Adrie VERHOEVEN ◽  
Ina KALKMAN ◽  
Hans JANSEN
Keyword(s):  
Hepatic Lipase ◽  
Rat Hepatocytes ◽  
Underlying Mechanism ◽  
Ionophore A23187 ◽  
Adrenergic Stimulation ◽  
Similar Reduction ◽  
Isolated Rat Hepatocytes ◽  
Intracellular Degradation ◽  
Subtype B ◽  
Catalytically Active

In rats, the daily changes in hepatic lipase (HL) activity in the liver follow the diurnal rhythm of the catecholamines. To study the underlying mechanism, the effect of adrenaline on maturation and secretion of HL was determined in freshly isolated rat hepatocytes. Adrenaline (10 μM) acutely inhibited the secretion of HL. This effect was abolished by 0.1 μM prazosin, but not by 1 μM propranolol, indicating the involvement of the α1-adrenergic pathway. Prazosin was at least 1000-fold more potent than WB4101, a selective α1A-antagonist. Adrenaline had no effect on HL secretion in hepatocytes pretreated with chloroethylclonidine, an irreversible α1B-selective antagonist. Inhibition of HL was not induced by 10 μM methoxamine, a α1A-selective agonist. Thus, adrenaline inhibited HL secretion through activation of the α1-adrenoceptors subtype B, which have been shown to signal through Ca2+ as well as cAMP. A similar reduction in HL secretion was induced by the Ca2+-mobilizing hormones angiotensin II (100 nM) and vasopressin (12 nM), the Ca2+ ionophore A23187 (2 μM), and by thapsigargin (1 μM), which inhibits the ER Ca2+-ATPase pump. HL secretion was unaffected by elevating cAMP with 10 μM forskolin or 1 μM 8-Br-cAMP. These results suggest that the α1B-adrenergic effects on HL expression are mainly mediated through elevation of intracellular Ca2+. Chelation of extracellular Ca2+ and subsequent lowering of intracellular Ca2+ with EGTA also inhibited HL secretion. In pulse-chase experiments, adrenaline was shown to inhibit the maturation of HL from the 53 kDa, Endo H-sensitive precursor to the Endo H-resistant, catalytically active protein of 58 kDa. In addition, adrenaline induced intracellular degradation of newly synthesized HL. Similar post-translational effects, both qualitatively and quantitatively, were observed with A23187, thapsigargin and EGTA. We conclude that the inhibition of HL maturation and increase in intracellular degradation induced by catecholamines, A23187, thapsigargin and EGTA is evoked by changes in Ca2+ homoeostasis, possibly through lowering ER Ca2+.

Sign in / Sign up

Export Citation Format

Share Document