FREE FATTY ACID METABOLISM IN CHINESE HAMSTERS

1966 ◽  
Vol 44 (1) ◽  
pp. 47-57 ◽  
Author(s):  
James Campbell ◽  
G. R. Green
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Spontaneous Diabetes ◽  
Chinese Hamster ◽  
Diabetic Rats ◽  
Epididymal Adipose Tissue ◽  
Time Interval ◽  
Adipose Tissues ◽  
Chinese Hamsters

In normal Chinese hamsters (Cricetulus griseus) the mean concentration of free fatty acids (FFA) in serum varied from group to group, but was (i) consistently 4 to 9 times greater than in rats, dogs, or man; (ii) slightly higher than in Syrian hamsters; (iii) two- to four-fold higher than in fasting or alloxan-diabetic rats. The epididymal adipose tissue of the Chinese hamster (i) had initial concentrations of FFA comparable to those in the rat and Syrian hamster; (ii) released, in the same time interval, 8- to 10-fold more FFA in vitro than this tissue of the rat; (iii) had higher concentrations of FFA after incubation than the incubated tissue of the rat. The retroperitoneal (perirenal) adipose tissue of the Chinese hamster was less active in release of fatty acids in vitro than the epididymal, but was, however, more active than the epididymal adipose tissue of the rat. These characteristics of FFA metabolism in the Chinese hamster were apparently attributable to species, not to age, diet, or sex. In the Chinese hamster, the weight of the epididymal adipose tissue per gram of body was relatively high. It appears that in this species the rate of release of fatty acids from adipose tissue is great, leading to high FFA concentrations in serum.In Chinese hamster and rat adipose tissues in vitro, glucose and insulin (separately) reduced the rate of release of FFA and the amount of FFA in the tissues, but glucose and insulin together produced the greatest reductions. The net reduction in FFA release by glucose and insulin in vitro was greater in tissue from the Chinese hamster. Insulin markedly increased glucose uptake by the adipose tissues of both species. The possible relation of the results to spontaneous diabetes in the Chinese hamster is discussed.

THE EFFECT OF VARIOUS SACCHARIDES ON THE RELEASE OF NON ESTERIFIED FATTY ACIDS FROM ADIPOSE TISSUE IN VITRO

1962 ◽  
Vol 40 (4) ◽  
pp. 455-458 ◽  
Author(s):  
W. F. Perry ◽  
R. J. Tjaden
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Incubation Medium ◽  
Epididymal Adipose Tissue ◽  
Tissue Cell ◽  
Glycerol Phosphate ◽  
Esterified Fatty Acids ◽  
Adipose Tissue Cell ◽  
Other Substances

Rat epididymal adipose tissue was incubated in a phosphate–albumin medium to ascertain the effect of various saccharides and other substances on the release of non-esterified fatty acids (NEFA) into the medium. It was found that incubation with glucose, mannose, fructose, and 2-deoxy glucose resulted in less release of NEFA from the tissue into the incubation medium. Incubation with galactose, sucrose, lactose, D-ribose, D-xylose, L-xylose, D-arabinose, L-arabinose, D-lyxose, sodium pyruvate, glycerol, and glycerol phosphate showed no differences from the control in release of NEFA into the incubation medium. These results are consistent with the theory that the NEFA-lowering action of glucose is due to esterification of free fatty acid within the adipose tissue cell by glycerol phosphate.

Lipogenesis in the sand rat (Psammomys obesus)

1983 ◽  
Vol 244 (5) ◽  
pp. E480-E486 ◽  
Author(s):  
B. Kalderon ◽  
J. H. Adler ◽  
E. Levy ◽  
A. Gutman
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Fatty Acid Synthetase ◽  
Epididymal Adipose Tissue ◽  
Albino Rats ◽  
Hepatic Lipogenesis ◽  
Very Low Density Lipoproteins ◽  
Sand Rat

Synthesis of fatty acids was measured in the liver and in epididymal adipose tissue of sand rats and albino rats. In chow-fed sand rats the rate of hepatic lipogenesis, as measured by the incorporation of 3H2O into fatty acids, was four- to sevenfold higher than in albino rats and in sand rats on a low-calorie saltbush diet. The contribution of [14C]glucose to lipogenesis in sand rat liver was lower than in albino rats. In fed sand rats lipogenesis incorporating 3H2O was stimulated by casein but not by glucose. In adipose tissue, lipogenesis measured 1 h after administration of 3H2O was much lower in sand rats than in albino rats. In vitro incorporation of [14C]glucose or acetate into adipose tissue fatty acids was negligible. In adipose tissue, uptake of very-low-density lipoproteins (VLDL) and lipoprotein lipase activity were sevenfold higher than in albino rats. Activities of NADP-malate dehydrogenase, acetyl CoA carboxylase, and fatty acid synthetase were considerably higher in the liver of chow-fed sand rats than in albino rats. It was concluded that obesity in sand rats originates from hepatic lipogenesis without a significant contribution of local fatty acid synthesis in adipose tissue.

THE EFFECT OF VARIOUS SACCHARIDES ON THE RELEASE OF NON ESTERIFIED FATTY ACIDS FROM ADIPOSE TISSUE IN VITRO

1962 ◽  
Vol 40 (1) ◽  
pp. 455-458
Author(s):  
W. F. Perry ◽  
R. J. Tjaden
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Incubation Medium ◽  
Epididymal Adipose Tissue ◽  
Tissue Cell ◽  
Glycerol Phosphate ◽  
Esterified Fatty Acids ◽  
Adipose Tissue Cell ◽  
Other Substances

Rat epididymal adipose tissue was incubated in a phosphate–albumin medium to ascertain the effect of various saccharides and other substances on the release of non-esterified fatty acids (NEFA) into the medium. It was found that incubation with glucose, mannose, fructose, and 2-deoxy glucose resulted in less release of NEFA from the tissue into the incubation medium. Incubation with galactose, sucrose, lactose, D-ribose, D-xylose, L-xylose, D-arabinose, L-arabinose, D-lyxose, sodium pyruvate, glycerol, and glycerol phosphate showed no differences from the control in release of NEFA into the incubation medium. These results are consistent with the theory that the NEFA-lowering action of glucose is due to esterification of free fatty acid within the adipose tissue cell by glycerol phosphate.

scholarly journals Studies on the conversion of pyruvate into fatty acids in white adipose tissue. Effects of insulin, alloxan-diabetes and starvation

1971 ◽  
Vol 124 (3) ◽  
pp. 615-621 ◽  
Author(s):  
Mitchell L. Halperin
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Insulin Treatment ◽  
Acid Synthesis ◽  
Diabetic Rats ◽  
Epididymal Adipose Tissue ◽  
Lag Phase ◽  
Metabolic States ◽  
Normal Rat

The effect of insulin on the conversion of pyruvate into fatty acids in the presence and in the absence of glucose was studied in epididymal adipose tissue of the rat. 1. In adipose tissue from the normal rat, conversion of pyruvate into fatty acids is directly related to its concentration, the maximal rates occurring with 40mm- and the half-maximal rates with approx. 4mm-pyruvate. Insulin treatment did not greatly influence the maximal rates, but the half-maximal rates were at much lower pyruvate concentrations. This effect of insulin could be seen with physiological concentrations of this hormone (50–100μunits/ml). 2. In adipose tissue from acute-alloxan-diabetic and 36h-starved rats the conversion of pyruvate into fatty acids was almost zero until its concentration exceeded 3mm and then increased markedly as the concentration of pyruvate was increased. The lag phase of this S-shaped curve was decreased but not eliminated when insulin was present. This could account for the very low rates of glucose conversion into fatty acids in these metabolic states. Maximum rates of fatty acid synthesis were similar in the presence and in the absence of insulin, but only when 30–40mm-pyruvate was employed. Re-feeding of the starved rats or insulin treatment of the diabetic rats in vivo for several days restored these patterns to normal.

Cold effects in rat: plasma and adipose tissue free fatty acids and adipose lipase

1963 ◽  
Vol 204 (1) ◽  
pp. 157-164 ◽  
Author(s):  
Samuel Mallov
Keyword(s):  
Adipose Tissue ◽  
Lipolytic Activity ◽  
Rat Plasma ◽  
Epididymal Adipose Tissue ◽  
Albino Rats ◽  
Adipose Tissues ◽  
Tissue Sections ◽  
Tissue Homogenates ◽  
Increased Activity

Male albino rats were exposed to cold or kept at room temperature for 1–24 hr. Plasmas and epididymal adipose tissues were analyzed for free fatty acid (FFA) concentrations and lipolytic activities of intact sections and homogenates, as well as release of FFA by adipose tissues, determined in vitro. Plasmas of rats exposed to cold had significantly higher FFA levels than did plasmas from controls, and intact epididymal adipose tissue sections from cold-exposed rats had higher FFA concentrations, released greater quantities of FFA, and manifested higher lipase activities in the presence of activated triglyceride substrate than did sections from control rats. Exposure to cold may increase FFA mobilization from adipose tissues as a result of enhanced lipolytic activity, due to lipase activation by catecholamines released from adrenals and sympathetic nerve endings. The enzyme activated did not possess several of the properties characteristic of lipoprotein lipase. Tissue homogenates did not manifest increased activity after cold exposure, possibly as a result of activation by the homogenization process itself.

Effect of sucrose-induced overfeeding on brown adipose tissue—With special reference to in vitro thermogenesis and fatty acids compositions

1995 ◽  
Vol 20 (6) ◽  
pp. 477-484 ◽  
Author(s):  
Akihiro Kuroshima ◽  
Tomie Ohno ◽  
Mitsuru Moriya ◽  
Hiroshi Ohinata ◽  
Takehiro Yahata ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Special Reference ◽  
Brown Adipose

Metabolic influences on enzymes of glycogen synthesis and breakdown in adipose tissue

1964 ◽  
Vol 207 (6) ◽  
pp. 1215-1220 ◽  
Author(s):  
Alisa Gutman ◽  
Eleazar Shafrir
Keyword(s):  
Adipose Tissue ◽  
Protein Content ◽  
Glycogen Synthesis ◽  
Total Activity ◽  
Epididymal Adipose Tissue ◽  
Control Value ◽  
Prolonged Fast ◽  
Rat Adipose Tissue

Rat adipose tissue from different body sites was shown to contain uridine diphosphoglucose (UDPG)-transglucosylase activity, which on the basis of protein content was comparable to or higher than that reported for muscle or liver. In epididymal adipose tissue, the activity of UDPG-glycogen transglucosylase and phosphorylase, as well as the content of glycogen per wet weight, decreased with increasing age of the animals in parallel with the decrease of tissue protein content. On prolonged fast the activity of UDPG-glycogen transglucosylase and phosphorylase per milligram protein dropped by 25–50% of the control value. On refeeding, the extent of changes was variable but, in general, at 24 hr control or higher levels of activity were reached and at 48 hr the activities were elevated. The ratio of glucose 6-phosphate independent activity of UDPG-glycogen transglucosylase to total activity was not affected by fasting and refeeding or by the administration of glucose with insulin. In adrenalectomized rats, with high adipose tissue glycogen, no change in UDPG-glycogen transglucosylase was found, whereas the levels of phosphorylase were elevated. Epinephrine in vivo and in vitro did not affect the activity of UDPG-glycogen transglucosylase of adipose tissue.

Adipose tissue in experimental nephrotic syndrome

1963 ◽  
Vol 205 (4) ◽  
pp. 702-706 ◽  
Author(s):  
Alisa Gutman ◽  
Eleazar Shafrir
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Nephrotic Syndrome ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Lipoprotein Lipase ◽  
Epididymal Adipose Tissue ◽  
Adequate Nutrition ◽  
Defective Metabolism ◽  
Inadequate Food Intake

Epididymal adipose tissue of aminonucleoside-treated rats, investigated 3 to 6 days after induction of the nephrotic syndrome, had low glycogen levels and showed impaired esterification of free fatty acids and assimilation of lipoprotein triglyceride and markedly reduced liberation of lipoprotein lipase. These results were found to be influenced by the inadequate food intake of the acutely nephrotic animals and comparable to the values of control rats fasted for 2 days. On return to adequate nutrition, which occurred 12–20 days after aminonucleoside treatment, adipose tissue glycogen and free fatty acid assimilation returned toward normal levels but lipoprotein-lipase liberation remained below normal. In rats rendered nephrotic by antikidney serum, the assimilation of free fatty acids and lipoprotein-triglyceride by adipose tissue was impaired in spite of only minor reduction in food consumption. The results indicate that the defective metabolism of adipose tissue in nephrotic animals may be contributory to the nephrotic hypertriglyceridemia.

CONVERSION OF METHIONINE AND THREONINE TO FATTY ACIDS BY ADIPOSE TISSUE

1963 ◽  
Vol 41 (1) ◽  
pp. 269-273 ◽  
Author(s):  
D. D. Feller ◽  
E. Feist
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Epididymal Adipose Tissue

Epididymal adipose tissue was incubated with uniformly labelled (14C)-methionine, (2-14C)-methionine, and uniformly labelled (14C)-threonine. Each of these compounds is actively metabolized by adipose tissue, as evidenced by the generation of 14CO2 and (14C)-fatty acid. Evidence was gathered in regard to the intermediary pathways by which these amino acids are utilized by adipose tissue and the general conclusion is drawn that these pathways are similar to those postulated for other tissues. These experiments further emphasize the central role that propionate plays in adipose tissue lipogenesis.

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