Control of plasma levels of growth hormone, glucagon and insulin in ducklings: roles of free fatty acids and somatostatin

1985 ◽  
Vol 106 (1) ◽  
pp. 21-25 ◽  
Author(s):  
Ch. Foltzer ◽  
M. Th. Strosser ◽  
S. Harvey ◽  
P. Mialhe
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Free Fatty Acids ◽  
Glucagon Secretion ◽  
Inhibitory Effect ◽  
Immunoreactive Insulin ◽  
Plasma Ffa ◽  
Plasma Gh ◽  
Glucagon And Insulin ◽  
Somatostatin 14

ABSTRACT The effects of plasma free fatty acids (FFA) and somatostatin-14 (S-14) on concentrations of plasma GH, glucagon and insulin were investigated in juvenile ducks. Oleic acid, S-14 or both were infused into 4- to 7-week-old birds and plasma GH, glucagon-like immunoreactivity (GLI), immunoreactive insulin (IRI) and FFA were measured. An increase in plasma GH and a decrease in GLI but no change in IRI was observed after infusion of 9 mg oleic acid/kg per min. A decrease in plasma GH, FFA and IRI and an increase in plasma GLI was seen after infusion of 800 ng S–14/kg per min. These effects of S-14 on IRI and GLI were abolished when S-14 was infused simultaneously with oleic acid. It is concluded that FFA have a direct stimulatory effect on GH secretion and an inhibitory effect on glucagon secretion. Somatostatin-14 directly inhibits the secretion of GH and its stimulatory effect on the secretion of glucagon is mediated by a depression in concentrations of plasma FFA. Finally, S-14 has no effect on plasma insulin when basal levels of plasma FFA are maintained. J. Endocr. (1985) 106, 21–25

THE RESPONSE OF PLASMA SUGAR, FREE FATTY ACIDS, 11-HYDROXYCORTICOSTEROIDS AND GROWTH HORMONE TO INSULIN-INDUCED HYPOGLYCAEMIA AND VASOPRESSIN IN PRIMARY MYXOEDEMA

1970 ◽  
Vol 48 (3) ◽  
pp. 389-400 ◽  
Author(s):  
F. P. VINCE ◽  
BARBARA J. BOUCHER ◽  
R. D. COHEN ◽  
JEAN GODFREY
Keyword(s):  
Fatty Acids ◽  
Growth Hormone ◽  
Free Fatty Acids ◽  
Normal Subjects ◽  
Pituitary Function ◽  
Hypothalamic Dysfunction ◽  
Lysine Vasopressin ◽  
Before And After ◽  
Plasma Ffa ◽  
Plasma Gh

SUMMARY The plasma sugar, free fatty acids (FFA), 11-hydroxycorticosteroids (11-OHCS) and growth hormone (GH) response to insulin-induced hypoglycaemia, have been studied in 19 patients with primary myxoedema and 13 normal subjects. Nine of the myxoedematous patients were restudied after treatment. The plasma 11-OHCS response to lysine vasopressin (LVP) was studied in the myxoedematous subjects and again in eight of them after treatment. In myxoedema the plasma sugar falls to a lesser extent and more slowly in response to insulin than normal and takes longer to recover. The fall in plasma FFA is not different from normal, but recovery of plasma FFA is delayed. The responses to insulin-induced hypoglycaemia of plasma GH and 11-OHCS may be smaller than normal in myxoedema and tend to improve on treatment. Altered GH and 11-OHCS responses to insulin-induced hypoglycaemia in myxoedema are not necessarily due to pituitary or hypothalamic dysfunction. No difference was found in the response of plasma 11-OHCS to LVP before and after treatment. Pituitary function cannot be fully assessed in the presence of hypothyroidism.

Free fatty acids and pancreatic function in the duck

1986 ◽  
Vol 112 (1) ◽  
pp. 100-104 ◽  
Author(s):  
R. Gross ◽  
P. Mialhe
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Inhibitory Effect ◽  
Feedback Mechanism ◽  
Pancreatic Function ◽  
Morphological Evidence ◽  
A Cell ◽  
Glucagon And Insulin

Abstract. The isolated perfused duck pancreas was used to study the effect of free fatty acids (FFA) on pancreatic function in vitro and to determine whether the FFA-glucagon negative feedback mechanism resulted from a direct inhibitory effect of FFA on the pancreatic A cell. Oleate, 2 mmol/l, increased the output rates of pancreatic somatostatin, glucagon and insulin. As there is poor morphological evidence in the duck for somatostatin to act as a paracrine intra-islet modulator, we reproduced in the pancreatico-duodenal artery, the rise in somatostatin level obtained in the pancreatic effluent after oleate. In these conditions the rises in glucagon and insulin secretions after oleate treatment were, respectively, reversed and suppressed, thereby reproducing observations previously made in vivo. Consequently, we may assume that the negative FFA-glucagon feedback mechanism that operates in vivo for physiological FFA variations does not result from a direct effect of FFA on the A cell, but may rather be mediated by an increase in pancreatic somatostatin secretion.

Source of plasma free fatty acids in dogs receiving fat emulsion and heparin

1963 ◽  
Vol 204 (4) ◽  
pp. 691-695 ◽  
Author(s):  
H. C. Meng ◽  
B. Edgren
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Lipolytic Activity ◽  
Blocking Agent ◽  
Fat Emulsion ◽  
Similar Reduction ◽  
Plasma Free Fatty Acids ◽  
Fat Infusion ◽  
Plasma Ffa ◽  
Slight Rise

Unanesthetized dogs were given either 3.0 g fat/kg as a 20% fat emulsion or heparin (2 mg/kg) intravenously or both. Plasma free fatty acids (FFA) and lipolytic activity were determined at intervals. In some experiments hexamethonium (5 mg/kg), a sympathetic ganglionic blocking agent, was administered intravenously either before or after fat or heparin. In fasting dogs fat infusion produced a moderate and heparin caused a slight rise in plasma FFA. Heparin given during lipemia produced a marked elevation of plasma FFA. The plasma lipolytic activity was increased after fat emulsion or heparin. Hexamethonium reduced the fasting plasma FFA about 70% or 0.40–0.6 mEq/liter. A similar reduction of plasma FFA also was observed when hexamethonium was administered during fat infusion or after heparin. Hexamethonium did not affect the increase in plasma lipolytic activity following the administration of fat emulsion or heparin. It seems probable that the increase in plasma FFA observed after intravenous infusion of fat emulsion or heparin is mainly due to the result of intravascular lipolysis.

Free fatty acids normalize a rosiglitazone-induced visfatin release

2006 ◽  
Vol 291 (5) ◽  
pp. E885-E890 ◽  
Author(s):  
Dominik G. Haider ◽  
Friedrich Mittermayer ◽  
Georg Schaller ◽  
Michaela Artwohl ◽  
Sabina M. Baumgartner-Parzer ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Term Treatment ◽  
Double Blind ◽  
Lipid Infusion ◽  
Major Mechanism ◽  
Insulin Mimetic ◽  
Long Term Treatment ◽  
Plasma Ffa

The detrimental effect of elevated free fatty acids (FFAs) on insulin sensitivity can be improved by thiazolidinediones (TZDs) in patients with type 2 diabetes mellitus. It is unknown whether this salutary action of TZD is associated with altered release of the insulin-mimetic adipocytokine visfatin. In this study, we investigated whether visfatin concentrations are altered by FFA and TZD treatment. In a randomized, double-blind, placebo-controlled, parallel-group study 16 healthy volunteers received an infusion of triglycerides/heparin to increase plasma FFA after 3 wk of treatment with rosiglitazone (8 mg/day, n = 8) or placebo ( n = 8), and circulating plasma visfatin was measured. As a corollary, human adipocytes were incubated with synthetic fatty acids and rosiglitazone to assess visfatin release in vitro. The results were that rosiglitazone treatment increased systemic plasma visfatin concentrations from 0.6 ± 0.1 to 1.7 ± 0.2 ng/ml ( P < 0.01). Lipid infusion caused a marked elevation of plasma FFA but had no effect on circulating visfatin in controls. In contrast, elevated visfatin concentrations in subjects receiving rosiglitazone were normalized by lipid infusion. In isolated adipocytes, visfatin was released into supernatant medium by acute addition and long-term treatment of rosiglitazone. This secretion was blocked by synthetic fatty acids and by inhibition of phosphatidylinositol 3-kinase or Akt. In conclusion, release of the insulin-mimetic visfatin may represent a major mechanism of metabolic TZD action. The presence of FFA antagonizes this action, which may have implications for visfatin bioactivity.

scholarly journals High rates of [1-14C]acetate incorporation into the lipid of isolated spinach chloroplasts

1976 ◽  
Vol 158 (3) ◽  
pp. 593-601 ◽  
Author(s):  
P G Roughan ◽  
C R Slack ◽  
R Holland
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Palmitic Acid ◽  
Free Fatty Acids ◽  
Acid Synthesis ◽  
Polar Lipids ◽  
Acetate Incorporation ◽  
Spinach Chloroplasts ◽  
Triton X

Spinach chloroplasts, isolated by techniques yielding preparations with high O2- evolving activity, showed rates of light-dependent acetate incorporation into lipids 3-4 fold higher than any previously reported. Incorporation rates as high as 500 nmol of acetate/h per mg of chlorophyll were measured in buffered sorbitol solutions containing only NaHCO3 and [1-14C]acetate, and as high as 800 nmol/h per mg of chlorophyll when 0.13 mM-Triton X-100 was also included in the reaction media. The fatty acids synthesized were predominantly oleic (70-80% of the total fatty acid radioactivity) and palmitic (20-25%) with only minor amounts (1-5%) of linoleic acid. Linolenic acid synthesis was not detected in the system in vitro. Free fatty acids accounted for 70-90% of the radioactivity incorporated and the remainder was shared fairly evenly between 1,2-diacylglycerols and polar lipids. Oleic acid constituted 80-90% of the free fatty acids synthesized, but the diacylglycerols and polar lipids contained slightly more palmitic acid than oleic acid. Triton X-100 stimulated the synthesis of diacylglycerols 3-6 fold, but stimulated free fatty acid synthesis only 1-1.5-fold. Added glycerol 1-phosphate stimulated both the synthesis of diacylglycerols and palmitic acid relative to oleic acid, but did not increase acetate incorporation into total chloroplast lipids. CoA and ATP, when added separately, stimulated acetate incorporation into chloroplast lipids to variable extents and had no effect on the types of lipid synthesized, but when added together resulted in 34% of the incorporated acetate appearing in long-chain acyl-CoA. Pyruvate was a much less effective precursor of chloroplast fatty acids than was acetate.

Central and peripheral adrenoceptors affect glucose, free fatty acids, and insulin in exercising rats

1988 ◽  
Vol 255 (4) ◽  
pp. R547-R556 ◽  
Author(s):  
A. J. Scheurink ◽  
A. B. Steffens ◽  
L. Benthem
Keyword(s):  
Fatty Acids ◽  
Blood Glucose ◽  
Free Fatty Acids ◽  
Blood Samples ◽  
Beta Adrenoceptor ◽  
Plasma Ffa ◽  
Glucose Plasma ◽  
Exercise Induced ◽  
Counter Current ◽  
Lateral Area

The effects of intravenously and intrahypothalamically administered alpha- and beta-adrenoceptor antagonists on exercise-induced alterations in blood glucose, plasma free fatty acids (FFA), and insulin were investigated in rats. Exercise consisted of strenuous swimming against a counter current for 15 min. Before, during, and after swimming, blood samples were withdrawn through a permanent heart catheter. Intravenous administration of the alpha-blocker phentolamine led to a reduction in glucose and a substantial increase in insulin levels. Infusion of phentolamine through permanent bilateral cannulas into either the ventromedial or lateral area of the hypothalamus (VMH and LHA, respectively) completely prevented the increase in glucose while the decline in insulin was unaffected. Infusion of phentolamine into the VMH caused much higher plasma FFA levels than in controls. The beta-blocker timolol given intravenously caused a delayed increase in glucose and prevented the increase in FFA. Infusion of timolol into either VMH or LHA caused a delay in the increase in both glucose and FFA. The results suggest that 1) both peripheral and hypothalamic adrenoceptors are involved in energy metabolism during exercise and 2) FFA, glucose, and insulin concentrations in blood are independently regulated by VMH and LHA.

scholarly journals Effects of free fatty acids on hepatic glycogenolysis and gluconeogenesis in conscious dogs

2002 ◽  
Vol 282 (2) ◽  
pp. E402-E411 ◽  
Author(s):  
Chang An Chu ◽  
Stephanie M. Sherck ◽  
Kayano Igawa ◽  
Dana K. Sindelar ◽  
Doss W. Neal ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Blood Glucose ◽  
Blood Glucose Level ◽  
Free Fatty Acids ◽  
Glucose Level ◽  
Conscious Dogs ◽  
Arterial Blood ◽  
Plasma Ffa ◽  
Arterial Plasma ◽  
Arterial Blood Glucose

The aim of this study was to determine the effect of high levels of free fatty acids (FFA) and/or hyperglycemia on hepatic glycogenolysis and gluconeogenesis. Intralipid was infused peripherally in 18-h-fasted conscious dogs maintained on a pancreatic clamp in the presence (FFA + HG) or absence (FFA + EuG) of hyperglycemia. In the control studies, Intralipid was not infused, and euglycemia (EuG) or hyperglycemia (HG) was maintained. Insulin and glucagon were clamped at basal levels in all four groups. The arterial blood glucose level increased by 50% in the HG and FFA + HG groups. It did not change in the EuG and FFA + EuG groups. Arterial plasma FFA increased by ∼140% in the FFA + EuG and FFA + HG groups but did not change significantly either in the EuG or HG groups. Arterial glycerol levels increased by ∼150% in both groups. Overall (3-h) net hepatic glycogenolysis was 196 ± 26 mg/kg in the EuG group. It decreased by 96 ± 20, 82 ± 16, and 177 ± 22 mg/kg in the HG, FFA + EuG, and FFA + HG groups, respectively. Overall (3-h) hepatic gluconeogenic flux was 128 ± 22 mg/kg in the EuG group, but it was suppressed by 30 ± 9 mg/kg in response to hyperglycemia. It was increased by 59 ± 12 and 56 ± 10 mg/kg in the FFA + EuG and FFA + HG groups, respectively. In conclusion, an increase in plasma FFA and glycerol significantly inhibited hepatic glycogenolysis and markedly stimulated hepatic gluconeogenesis.

Factors Affecting Plasma Free Fatty Acids Rise during Hemodialysis

1988 ◽  
Vol 11 (2) ◽  
pp. 95-98 ◽  
Author(s):  
G. Mingardi ◽  
E. Branca ◽  
M. Cini ◽  
A.M. Codegoni ◽  
G. Mecca ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Plasma Lipids ◽  
Unknown Mechanism ◽  
Factors Affecting ◽  
Plasma Free Fatty Acids ◽  
Plasma Triglycerides ◽  
Plasma Ffa ◽  
Acute Changes

We studied the mechanisms responsible for causing acute changes in plasma lipids during hemodialysis. Dialysis decreased plasma triglycerides to the same extent as when heparin was given without dialysis. Cholesterol increased in proportion to hemoconcentration. Plasma free fatty acids (FFA) levels were also increased, but more so than with heparin alone. Glucose and acetate did not play a role, nor did carnitine loss, and hemofiltration elicited similar effects. The rise in plasma FFA is therefore likely to be caused by other as yet unknown mechanism.

Epinephrine-insulin antagonism on free fatty acid release

1961 ◽  
Vol 201 (5) ◽  
pp. 815-818 ◽  
Author(s):  
John J. Spitzer ◽  
William T. McElroy
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Free Fatty Acids ◽  
Blood Sugar ◽  
Drug Administration ◽  
Hepatic Uptake ◽  
Fatty Acid Release ◽  
Plasma Ffa ◽  
Acid Release

The effects of epinephrine or norepinephrine were studied in dogs receiving insulin plus glucose prior to and during administration of the amine. Epinephrine caused a significantly smaller elevation of free fatty acids (FFA) with than without insulin plus glucose administration. Blood sugar responses were quantitatively similar. Epinephrine increased both hepatic uptake of FFA and hepatic release of glucose; these changes were similar to the ones found previously in dogs not receiving insulin plus glucose. The action of norepinephrine on elevating plasma FFA was only slightly and not significantly affected by the administration of insulin plus glucose. When the order of drug administration was reversed, infusion of insulin plus glucose lowered plasma FFA levels and hepatic FFA uptake in animals already receiving either epinephrine or nonepinephrine.

Composition of Lipids of Piqui (Caryocar coriaceum Wittm.) Seed and Pulp Oil

1989 ◽  
Vol 44 (9-10) ◽  
pp. 739-742 ◽  
Author(s):  
Heidrun Dresen ◽  
R. B. N. Prasad ◽  
Paul-Gerhard Gülz
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Free Fatty Acids ◽  
Molecular Species ◽  
Lipid Composition ◽  
Seed Oil ◽  
Sterol Fraction

Abstract The lipid composition of Piqui (Caryocar coriaceum) seed oil and pulp oil was analyzed and found to contain triacylglycerols (95.1/95.3%) as major components followed by free fatty acids (1.7/1.6%), diacylglycerols (1.6/1.5%), squalene (0.3/0.3%) and monoacylglycerols (0.1/0.1%). Phospholipids were found only in seed oil (0.2%). They were identified as phosphatidylethanolamine and phosphatidylinositol. The sterol fraction (0.1/0.1%) contained stigmasterol and β-sito-sterol. In seed oil triacylglycerols the C-53 molecular species were dominated (52.8%) follow ed by C-55 (37.7%), C-57 (6.9%) and C-51 (2.6%) in minor quantities. In pulp oil triacylglycerols C-55 (51.7%) was predominant followed by C-53 (30.6%) and C-57 (17.7%). Palmitic (16:0) and oleic (18:1) acids were always the major fatty acids in both oils. In seed oil their quantities were nearly the same, whereas in pulp oil oleic acid was predominant. Composition of Lipids of Piqui (Caryocar coriaceum Wittm.)

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