scholarly journals The effect of glucose, insulin and noradrenaline on lipolysis and on the concentrations of adenosine 3′:5′-cyclic monophosphate and adenosine 5′-triphosphate in adipose tissue

1973 ◽  
Vol 132 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Brian L. Knight ◽  
Jill Iliffe
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Cyclic Amp ◽  
Free Fatty Acids ◽  
Glycerol Release ◽  
Atp Production ◽  
Control Value ◽  
Atp Concentration ◽  
Effect Of Glucose ◽  
Peak Value

Glycerol release and tissue concentrations of ATP and cyclic AMP were followed during the incubation of adipose tissue with or without glucose, insulin and noradrenaline. Glucose plus insulin or, to a lesser extent, glucose alone increased the accumulation of glycerol during incubations both with and without noradrenaline by slowing the decline in the rate of glycerol release with time. Insulin alone decreased the accumulation by accelerating the fall in glycerol release. In the absence of noradrenaline, ATP and cyclic AMP concentrations were not significantly affected by insulin or glucose. With noradrenaline or noradrenaline plus insulin the ATP concentration gradually fell. With noradrenaline plus glucose the ATP concentration fell rapidly and then stabilized, or, if insulin was also present, returned to the control value. In the presence of noradrenaline, the concentration of cyclic AMP rose during the first 20min and then fell. Insulin lowered the peak concentration of cyclic AMP, but glucose had no effect either on the peak value or the fall in the concentration of the nucleotide. The increase and fall in the concentration of cyclic AMP with noradrenaline or noradrenaline plus insulin bore similarities to the increase and decline in the lipolytic rate in incubations without glucose. It is proposed that glucose stimulates ATP production by furnishing glycerol 1-phosphate and thus removing free fatty acids, but that it can influence lipolysis by a mechanism which is distinct from any which is mediated by free fatty acids, possibly by inhibiting the inactivation of the lipase.

The Relationship of Fasting Free Fatty Acids, Adipose Tissue, Insulin Resistance, and Fasting Glucose Concentrations with Subsequent ß-Cell Function in Nondiabetic Subjects

Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 1812-P
Author(s):  
MARIA D. HURTADO ◽  
J.D. ADAMS ◽  
MARCELLO C. LAURENTI ◽  
CHIARA DALLA MAN ◽  
CLAUDIO COBELLI ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Free Fatty Acids ◽  
Cell Function ◽  
Fasting Glucose ◽  
Relationship Of ◽  
The Relationship

scholarly journals Release of free fatty acids from adipose tissue obtained from newborn infants

1965 ◽  
Vol 6 (1) ◽  
pp. 91-95
Author(s):  
Milan Novák ◽  
Václav Melichar ◽  
Petr Hahn ◽  
Otakar Koldovský
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Free Fatty Acids ◽  
Newborn Infants

scholarly journals EFFECTS OF CORTISOL ON CULTURED RAT HEART CELLS

1973 ◽  
Vol 57 (1) ◽  
pp. 109-116 ◽  
Author(s):  
J. V. Anastasia ◽  
R. L. McCarl
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Oxidation ◽  
Growth Medium ◽  
Rat Heart ◽  
Acid Oxidation ◽  
Heart Cells ◽  
Atp Production ◽  
Rat Heart Cells

This paper reports the determination of the ability of rat heart cells in culture to release [14C]palmitate from its triglyceride and to oxidize this fatty acid and free [14C]palmitate to 14CO2 when the cells are actively beating and when they stop beating after aging in culture. In addition, the levels of glucose, glycogen, and ATP were determined to relate the concentration of these metabolites with beating and with cessation of beating. When young rat heart cells in culture are actively beating, they oxidize free fatty acids at a rate parallel with cellular ATP production. Both fatty acid oxidation and ATP production remain constant while the cells continue to beat. Furthermore, glucose is removed from the growth medium by the cells and stored as glycogen. When cultured cells stop beating, a decrease is seen in their ability to oxidize free fatty acids and to release them from their corresponding triglycerides. Concomitant with decreased fatty acid oxidation is a decrease in cellular levels of ATP until beating ceases. Midway between initiation of cultures and cessation of beating the cells begin to mobilize the stored glycogen. When the growth medium is supplemented with cortisol acetate and given to cultures which have ceased to beat, reinitiation of beating occurs. Furthermore, all decreases previously observed in ATP levels, fatty acid oxidation, and esterase activity are restored.

Fat Metabolism in Heavy Exercise

1980 ◽  
Vol 59 (6) ◽  
pp. 469-478 ◽  
Author(s):  
N. L. Jones ◽  
G. J. F. Heigenhauser ◽  
A. Kuksis ◽  
C. G. Matsos ◽  
J. R. Sutton ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Free Fatty Acids ◽  
Respiratory Exchange Ratio ◽  
Fat Metabolism ◽  
Maximum Power ◽  
Oxygen Intake ◽  
Heavy Exercise ◽  
Heavy Work ◽  
Adipose Tissue Lipolysis

1. To investigate differences between the metabolic effects of light and heavy exercise, five healthy males (mean maximal oxygen intake 3.92 litres/min) exercised for 40 min at 36% maximum power (light work) and 70% maximum power (heavy work) on separate days, after an overnight fast. 2. A steady state was achieved in both studies between 20 and 40 min in: oxygen intake (1.42 and 2.64 litres/min respectively); respiratory exchange ratio (0.89 and 1.01); plasma lactate concentration (1.78 and 9.94 mmol/l). 3. Plasma palmitate turnover rate (14C) was unchanged from resting values in light work but was decreased by 40% (from 104 ± 16 to 63 ± 8 μmol/min) in heavy work. Heavy work was associated with falls in the plasma concentrations of all free fatty acids measured: palmitic acid (C16:0), oleic acid (C18:1), stearic acid (C18:0), linoleic acid (C18:2) and palmitoleic acid (C16:1). 4. In contrast to the fall in palmitate turnover the increase in plasma glycerol was greater in heavy exercise (0.054–0.229 mmol/l) than in light exercise (0.053–0.094 mmol/l), suggesting that lipolysis was occurring which did not lead to influx of free fatty acids into plasma. 5. In light exercise fat metabolism may be controlled to favour adipose tissue lipolysis and extraction of free fatty acids by muscle from the circulation, whereas in heavy exercise adipose tissue lipolysis is inhibited and hydrolysis of muscle triglycerides may play a more important part. 6. The finding of a high respiratory exchange ratio may not exclude the use of fat as a major fuel source in exercise associated with lactate production.

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.

Importance of the Cyclic AMP Concentration for the Rate of Lipolysis in Human Adipose Tissue

1980 ◽  
Vol 59 (3) ◽  
pp. 199-201 ◽  
Author(s):  
P. Arner ◽  
J. Östman
Keyword(s):  
Adipose Tissue ◽  
Cyclic Amp ◽  
Subcutaneous Adipose Tissue ◽  
Human Adipose Tissue ◽  
Strong Positive Correlation ◽  
Glycerol Release ◽  
Two Parameters ◽  
Subcutaneous Adipose ◽  
The Relationship ◽  
Release Of Glycerol

1. The activation of lipolysis on incubation of human subcutaneous adipose tissue was examined in terms of the relationship between the release of glycerol and the concentration of tissue cyclic AMP. 2. A strong positive correlation was obtained between the maximum concentration of cyclic AMP and the rate of glycerol release in the presence of noradrenaline (r = 0.9), whereas, in the basal state, these two parameters were only weakly correlated (r = 0.45). 3. It appears that the noradrenaline-induced rate of lipolysis depends upon the maximal concentration of cyclic AMP that is present in human adipose tissue.

Effect of glucose on lipolysis and on release of lipolytic products in isolated adipocytes

1975 ◽  
Vol 228 (1) ◽  
pp. 92-97 ◽  
Author(s):  
C Naito ◽  
K Okada
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Free Glycerol ◽  
Adipose Tissues ◽  
Simple Diffusion ◽  
Retention Ratio ◽  
Total Mixture ◽  
Isolated Adipocytes ◽  
Effect Of Glucose ◽  
Measured Addition

Isolated adipocytes were prepared from epididymal adipose tissues removed from rats which had been fed or starved for 48 h (fed adipocytes or fasted adipocytes). These cells were incubated at 37 degrees C for 90 min in media containing 0, 3, or 30 mM glucose, with or without norepinephrine (1.0 mug/ml). Then the concentrations of free fatty acids (FFA) and free glycerol (FG) in the total mixture (medium plus cells) and in the medium alone were measured. Addition of glucose to the medium increased the total PG, presumably by increasing the basal lipolysis, and it decreased the intracellular retention ratio of FG (the ratio of intracellular FG to total FG). Addition of glucose did not change the total FFA, but decreased the FFA/FG ratio, presumably by increasing reesterification. The increase in FG and decrease in the FFA/FG ratio on addition of glucose were greater in fed than in fasted adipocytes. The intracellular retention ratio of FFA also decreased on addition of glucose. Glucose enhanced norepinephrine-induced lipolysis (release of free glycerol), and this effect of glucose was greater in fasted adipocytes. However, the increase in FFA in fasted adipocytes induced by norepinephrine was not altered by addition of glucose. In fed adipocytes norepinephrine decreased the total FFA in the presence of glucose. Reesterification of FFA following norepinephrine was increased by addition of glucose. Norepinephrine decreased the intracellular retention ratios of FG and FFA in the presence of glucose. These results suggest that the passage of the lipolytic products, FFA and FG, through the cell membranes may not occur by simple diffusion, but may require energy.

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