Abstract：
:The role of phosphodiesterase in glucagon resistance of large adipocytes was investigated. A comparison was made of phosphodiesterase activities of homogenates prepared from isolated small (mean diameter approximately 45 micro m) and large (mean diameter approximately 78 micro m) adipocytes, using various concentrations (5 x 10(-4) to 1 x 10(-7) M) of 3',5'-cAMP. Kinetic analyses revealed two distinct catalytic activities (high and low affinities) in both cell types; however, the activities of both high- and low-affinity enzymes were significantly elevated in large adipocytes. Lipolysis was measured in isolated adipocytes in the presence of different concentrations (0.1-0.6 mM) of the phosphodiesterase inhibitor aminophylline. Large adipocytes were less responsive to low levels of methylxanthine, suggesting that greater amounts of phosphodiesterase must be inhibited before lipolysis can be stimulated. To evaluate the influence of phosphodiesterase during glucagon-stimulated lipolysis, small and large adipocytes were incubated with a maximally effective concentration of glucagon (1.5 x 10(-6) M) in combination with various concentrations (0.1-0.6 mM) of aminophylline. Although the glucagon effect was potentiated in both cell types, the maximum lipolytic response of large adipocytes (at 0.4 mM aminophylline) was approximately 36% lower than that observed in small adipocytes (at 0.2 mM aminophylline). This reduction correlates closely with the decreased glucagon binding present in large cells; therefore, it appears that the glucagon-resistant state is adequately explained by elevations in phosphodiesterase levels and diminished glucagon-cell association.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
De Santis RA,Gorenstein T,Livingston JN,Lockwood DHsubject
Has Abstractpub_date
1974-01-01 00:00:00pages
33-8issue
1eissn
0022-2275issn
1539-7262journal_volume
15pub_type
杂志文章abstract：:Genome-wide association (GWA) studies represent a powerful strategy for identifying susceptibility genes for complex diseases in human populations but results must be confirmed and replicated. Because of the close homology between mouse and human genomes, the mouse can be used to add evidence to genes suggested by hum...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M009175
更新日期：2011-06-01 00:00:00
abstract：:We previously have shown that LDL-R354, a truncated low density lipoprotein (LDL) receptor, is a calcium binding protein. LDL-R354 is composed of the ligand binding domain and repeat A of the EGF precursor homology domain of the full-length human LDL receptor. We also found that Ca2+ was required for the interaction b...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1998-02-01 00:00:00
abstract：:Origins of hyperlipidemia and cholestasis that occur during pregnancy were investigated by examining expression of key elements related to plasma and hepatic cholesterol metabolism during pregnancy, lactation, and post-lactation in the rat model. Among major findings were: during pregnancy, the activities of hepatic 3...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1998-11-01 00:00:00
abstract：:Lymph chylomicrons of different sizes are known to be cleared at different rates, but the underlying mechanism for this effect has not been resolved. To investigate the differences in clearance rates between small and large particles, chylomicron-like lipid emulsions labeled with radioactive triolein and cholesteryl o...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-12-01 00:00:00
abstract：:Ceramides containing phytosphingosine as base and one of the fatty acids 16:0, 18:0, 20:0, 22:0, 23:0, and 24:0, were prepared by direct coupling in the presence of a mixed carbodiimide. The ceramides were analyzed as the 1,3,4-tri-O-trimethylsilyl ether derivatives by gas-liquid chromatography-mass spectrometry. Gas ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1970-05-01 00:00:00
abstract：:Mice with a targeted mutation of 3beta-hydroxysterol Delta(7)-reductase (Dhcr7) that cannot convert 7-dehydrocholesterol to cholesterol were used to identify the origin of fetal sterols. Because their heterozygous mothers synthesize cholesterol normally, virtually all sterols found in a Dhcr7 knockout fetus having a D...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M600141-JLR200
更新日期：2006-07-01 00:00:00
abstract：:Our objective was to establish the role of the apoprotein (apo) E phenotype in determining serum cholesterol levels in infants fed exclusively on high-fat, high-cholesterol human milk and in those fed a low-cholesterol, high-unsaturated fat formula. The total and lipoprotein cholesterol, apoB, and triglyceride concent...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1997-04-01 00:00:00
abstract：:Inhibition of Ehrlich ascites carcinoma respiration by aqueous extracts of oxidized linoleic or linolenic acid (aqueous emulsions UV-irradiated, 90 min) was associated entirely with relatively involatile compounds which were both thiobarbituric acid (TBA)-reactive and peroxidase-reactive. Inhibitory compounds were hea...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1966-05-01 00:00:00
abstract：:The total nitrogen and L-hydroxyproline concentrations of two intra-abdominal and two subcutaneous sites of adipose tissue were measured in male and female Wistar rats. At 100 g body weight the nitrogen concentration of intra-abdominal adipose tissue was slightly lower than that of subcutaneous adipose tissue. As age ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1970-07-01 00:00:00
abstract：:The dynamics of human apoE metabolism were explored by examining the effects of alimentary lipemia and postheparin lipolysis on the plasma level and lipoprotein distribution of apoE. In the studies of alimentary lipemia, fasting and postprandial plasma samples were obtained from five normal adult males, each of whom d...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1982-12-01 00:00:00
abstract：:HDL cholesterol levels are decreased in Crohn's disease, a tumor necrosis factor-alpha (TNF-alpha)-driven chronic inflammatory condition involving the gastrointestinal tract. ATP-binding cassette transporter A1 (ABCA1), one of several liver X receptor (LXR) target genes, is a cell surface transporter that mediates the...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M002410
更新日期：2010-06-01 00:00:00
abstract：:The conditions for the preparation of laurylsarcosyltaurine from lauric acid and sarcosyltaurine, a crystalline dipeptide, are described. The preparation of sarcosyltaurine from the reaction of taurine and the mixed anhydride of benzyloxycarbonylsarcosine and isobutyl chloroformate is also described. ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1976-03-01 00:00:00
abstract：:The inbred C57L strain but not the AKR strain of mice carry Lith genes that determine cholesterol gallstone susceptibility. When C57L mice are fed a lithogenic diet containing 15% fat, 1% cholesterol, and 0.5% cholic acid, gallbladder bile displays rapid cholesterol supersaturation, mucin gel accumulation, increases i...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1999-11-01 00:00:00
abstract：:Fatty acid compositions of glycerophosphatides of developing chick embryonic brain and liver were compared. In brain, ethanolamine and serine glycerophosphatides contained 30-40% polyunsaturated fatty acids, lecithin almost none (except for arachidonic). In the liver, these acids were equally distributed in the phosph...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1966-09-01 00:00:00
abstract：:The direct effect of apolipoprotein (apo) E on cholesteryl ester transfer protein (CETP) activity was studied using lipoproteins from a subject with apoE deficiency (Atherosclerosis. 1991. 88: 15-20) as a model system. The transfer of cholesteryl ester (CE) from discoidal bilayer particles (DBP) to very low density li...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1993-02-01 00:00:00
abstract：:Clock genes respond to external stimuli and exhibit circadian rhythms. This study investigated the expression of clock genes in the small intestine and their contribution in the regulation of nutrient absorption by enterocytes. We examined expression of clock genes and macronutrient transport proteins in the small int...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M900085-JLR200
更新日期：2009-09-01 00:00:00
abstract：:The inverse relationship between plasma levels of high density lipoprotein (HDL) and coronary heart disease rates has suggested that HDL might influence body stores of cholesterol. Therefore, we have investigated potential relationships between the parameters of body cholesterol metabolism and the plasma levels of HDL...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1985-09-01 00:00:00
abstract：:Different batches of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) had varying amounts of contaminants which appeared to affect systematic biological studies. This contaminant was separated by silica gel column chromatography followed by high performance liquid chromatography and identified as 1,3-distearoyl-glyce...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1980-01-01 00:00:00
abstract：:Boiled coffee contains an unidentified lipid that raises serum cholesterol. We studied the effects of the ingestion of coffee oil fractions of increasing purity in volunteers in order to identify the cholesterol-raising factor. In 15 volunteers who ingested 0.75 g/d of a non-triglyceride-fraction from coffee oil for 4...
journal_title：Journal of lipid research
pub_type： 临床试验,杂志文章,随机对照试验
doi：
更新日期：1994-04-01 00:00:00
abstract：:A variety of methods are currently used to analyze HL and LPL activities in mice. In search of a simple methodology, we analyzed mouse preheparin and postheparin plasma LPL and HL activities using specific polyclonal antibodies raised in rabbit against rat HL (anti-HL) and in goat against rat LPL (anti-LPL). As an alt...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.D700021-JLR200
更新日期：2007-12-01 00:00:00
abstract：:Rates of conversion of alpha-linolenic acid (alpha-LNA, 18:3n-3) to docosahexaenoic acid (DHA, 22:6n-3) by the mammalian brain and the brain's ability to upregulate these rates during dietary deprivation of n-3 polyunsaturated fatty acids (PUFAs) are unknown. To answer these questions, we measured conversion coefficie...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M600549-JLR200
更新日期：2007-05-01 00:00:00
abstract：:Nine even-numbered saturated (C4 to C20) and two unsaturated (C18:1, C18:2) cholesterol alkyl ethers were studied by differential scanning calorimetry, polarizing microscopy, and X-ray powder diffraction. Seven of the nine saturated ethers examined melt into stable liquid crystal mesophases. Mesophase transition tempe...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1983-05-01 00:00:00
abstract：:Analytical isoelectric focusing (IEF) has been applied to the study of the apolipoprotein components of rat serum high density and very low density lipoproteins. The apolipoproteins were separated on 7.5% polyacrylamide gels containing 6.8% urea, with a pH gradient of 4-6. The middle molecular weight range apolipoprot...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
abstract：:Previously, we have shown that lipid-free apoA-I, when incubated with fibroblasts, will produce lipoproteins of pre-alpha mobility (Asztalos, B. F., et al. 1997. Arterioscler. Thromb. Vasc. Biol. 17: 1630-1636). In order to understand the nature of these pre-alpha particles, we further characterized their lipid conten...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1998-08-01 00:00:00
abstract：:The time course of the clearance from the blood and the tissue localization of [14C]L-glucosylceramide, a nonmetabolizable enantiomorph of D-glucosylceramide that accumulates in Gaucher's disease, has been determined. 14C-labeled L-glucosylceramide injected intravenously in the form of micelles or liposomes is rapidly...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1987-08-01 00:00:00
abstract：:Cellular cholesterol is known to be under homeostatic control in nonsteroidogenic cells, and this intrigued us to understand how such control works in steroidogenic cells that additionally use cholesterol for steroid hormone synthesis. We employed primary culture of rat ovarian granulosa cells to study how steroidogen...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M030239
更新日期：2013-02-01 00:00:00
abstract：:The goal of this study was to determine whether apolipoprotein A-I (apoA-I) is lipidated before secretion by HepG2 cells. ApoA-I was extracted from microsomes after radiolabeling with [(35)S]Met/Cys. After ultracentrifugal flotation, d < 1.25 g/ml and d > 1.25 g/ml fractions were immunoprecipitated and analyzed by SDS...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2002-01-01 00:00:00
abstract：:A molecular model was built for human lecithin:cholesterol acyltransferase (LCAT) based upon the structural homology between this enzyme and lipases (Peelman et al. 1998. Prot. Sci. 7: 585-597). We proposed that LCAT belongs to the alpha/beta hydrolase fold family, and that the central domain of LCAT consists of a mix...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1999-01-01 00:00:00
abstract：:The technique of short bed--continuous development chromatography has been utilized to increase the separation of glycosphingolipids on high performance thin-layer chromatography plates. The theoretical goal of increasing separation of bands by decreasing solvent strength was achieved within a practical time span as a...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：:The proton NMR spectra of the N-methyl choline region of normal and lecithin:cholesterol acyltransferase (LCAT)-deficient lipoproteins and of egg yolk phosphatidylcholine-cholesterol 55:45 (mol %) vesicle mixtures have been examined in the presence and absence of manganous sulfate as a line-broadening reagent. Mangano...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1989-05-01 00:00:00
