Plasma somatostatin turnover rate and hormonal responses to feeding in chronically cold-exposed sheep

1991 ◽  
Vol 71 (4) ◽  
pp. 1087-1098
Author(s):  
R. A. Christensen ◽  
R. J. Christopherson ◽  
J. J. Kennelly ◽  
G. de Boer ◽  
G. J. Mears
Keyword(s):  
Growth Hormone ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Turnover Rate ◽  
Plasma Free Fatty Acid ◽  
Secretion Rate ◽  
Metabolic Clearance ◽  
Hormonal Responses ◽  
Key Words Cold ◽  
Somatostatin 14

Ten crossbred wether lambs (44.9 ± 1.0 kg) were housed for 9 wk in either a thermoneutral (TN) (20 °C) or cold (CC) (0 °C) environment and fed a pelleted barley:soybean meal diet (19.6% crude protein) at 28.8 g d−1 kg−1. Environmental temperature significantly altered mean concentrations of free fatty acid (TN 0.32 mM, CC 0.43 mM; P < 0.02, SEM = 0.01), insulin (TN 2.06 ng mL−1, CC 0.68 ng mL−1; P < 0.03, SEM = 0.10), and glucagon (TN 0.27 ng mL−1 CC 0.20 ng mL−1; P < 0.05, SEM = 0.01) but had no effect on glucose, somatostatin, or growth hormone. Glucose (P < 0.001) and insulin (P < 0.001) concentrations increased, whereas free fatty acid (P < 0.001) and growth hormone (P < 0.001) concentrations decreased after feeding. Somatostatin concentrations did not change postprandially. Following an injection of somatostatin-14 (1.13 ± 0.08 μg kg−1 BW), plasma-free fatty acid concentrations increased (P < 0.001) within 2 min and remained elevated for 30–75 min. Somatostatin-14 injection caused a transient (5–7 min) decrease in plasma insulin in both environments and glucagon in the TN environment. Somatostatin had a longer half-life, slower turnover rate, and reduced metabolic clearance and secretion rate (P < 0.05) in the cold environment, but the reduced secretion rate resulted in no change in basal concentrations of somatostatin. Key words: Cold, feeding, somatostatin, sheep, metabolic clearance rate

Effect of growth hormone of free fatty acid metabolism

1964 ◽  
Vol 206 (1) ◽  
pp. 174-178 ◽  
Author(s):  
Bertram Winkler ◽  
Robert Steele ◽  
Norman Altszuler ◽  
Richard C. de Bodo
Keyword(s):  
Growth Hormone ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Turnover Rate ◽  
Acid Metabolism ◽  
Plasma Free Fatty Acid ◽  
Transient Effect ◽  
Free Fatty Acid Metabolism ◽  
Plasma Ffa ◽  
Ffa Metabolism

Bovine growth hormone ( GH) was administered at 1 mg/kg day for various periods of time to normal dogs. The effects produced on plasma free fatty acid ( FFA) metabolism were studied in these animals, in the unanesthetized state, using palmitate-C14. At 3–9 hr following intravenous injection of growth hormone significant increase were observed in plasma FFA concentration, turnover rate, total amount of FFA oxidized to CO2, and per cent of total respiratory CO2 derived from FFA. FFA production was increased by GH; FFA uptake and oxidation increased in parallel with plasma FFA concentration and apparently were not affected directly by GH. Similar changes were observed after 2 days of GH. After 7 days of GH all these parameters returned to control values. The transient effect of GH on FFA metabolism is in contrast with its reported prolonged effects on fat metabolism; possible reasons for this discrepancy are discussed.

Plasma Free Fatty Acid Response to the Administration of Chorionic “Growth Hormone-Prolactin”

1966 ◽  
Vol 26 (4) ◽  
pp. 478-482 ◽  
Author(s):  
M. M. GRUMBACH ◽  
S. L. KAPLAN ◽  
C. L. ABRAMS ◽  
J. J. BELL ◽  
F. A. CONTE
Keyword(s):  
Growth Hormone ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Plasma Free Fatty Acid

Prevailing hyperglycemia is critical in the regulation of glucose metabolism during exercise in poorly controlled alloxan-diabetic dogs

2005 ◽  
Vol 98 (3) ◽  
pp. 930-939 ◽  
Author(s):  
Michael J. Christopher ◽  
Christian Rantzau ◽  
Glenn McConell ◽  
Bruce E. Kemp ◽  
Frank P. Alford
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Glucose Uptake ◽  
Plasma Glucose ◽  
Hepatic Glucose Production ◽  
Glucose Production ◽  
Plasma Free Fatty Acid ◽  
Glucose Turnover ◽  
Metabolic Clearance ◽  
Hepatic Glucose

The separate impacts of the chronic diabetic state and the prevailing hyperglycemia on plasma substrates and hormones, in vivo glucose turnover, and ex vivo skeletal muscle (SkM) during exercise were examined in the same six dogs before alloxan-induced diabetes (prealloxan) and after 4–5 wk of poorly controlled hyperglycemic diabetes (HGD) in the absence and presence of ∼300-min phlorizin-induced (glycosuria mediated) normoglycemia (NGD). For each treatment state, the ∼15-h-fasted dog underwent a primed continuous 150-min infusion of [3-3H]glucose, followed by a 30-min treadmill exercise test (∼65% maximal oxygen capacity), with SkM biopsies taken from the thigh (vastus lateralis) before and after exercise. In the HGD and NGD states, preexercise hepatic glucose production rose by 130 and 160%, and the metabolic clearance rate of glucose (MCRg) fell by 70 and 37%, respectively, compared with the corresponding prealloxan state, but the rates of glucose uptake into peripheral tissues (Rdtissue) and total glycolysis (GF) were unchanged, despite an increased availability of plasma free fatty acid in the NGD state. Exercise-induced increments in hepatic glucose production, Rdtissue, and plasma-derived GF were severely blunted by ∼30–50% in the NGD state, but increments in MCRg remained markedly reduced by ∼70–75% in both diabetic states. SkM intracellular glucose concentrations were significantly elevated only in the HGD state. Although Rdtissue during exercise in the diabetic states correlated positively with preexercise plasma glucose and insulin and GF and negatively with preexercise plasma free fatty acid, stepwise regression analysis revealed that an individual's preexercise glucose and GF accounted for 88% of Rdtissue during exercise. In conclusion, the prevailing hyperglycemia in poorly controlled diabetes is critical in maintaining a sufficient supply of plasma glucose for SkM glucose uptake during exercise. During phlorizin-induced NGD, increments in both Rdtissue and GF are impaired due to a diminished fuel supply from plasma glucose and a sustained reduction in increments of MCRg.

Independence of growth hormone effects on nitrogen retention and free fatty acid mobilization

1968 ◽  
Vol 46 (10) ◽  
pp. 1269-1272 ◽  
Author(s):  
Jose S. Cheng ◽  
Norman Kalant
Keyword(s):  
Growth Hormone ◽  
Oxygen Consumption ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Respiratory Quotient ◽  
Nitrogen Retention ◽  
Plasma Free Fatty Acid ◽  
Suppressive Effect ◽  
Nitrogen Excretion ◽  
Ad Libitum

Bovine growth hormone (4 mg) was injected subcutaneously into two groups of rats, one group limited-fed and the other fed ad libitum. Four hours later, the respiratory quotient was found to be lowered and the plasma free fatty acid (FFA) level elevated. The oxidation rate of orally administered 14C-tripalmitin to 14CO2 and the oxygen consumption rate were not affected. Growth hormone administered for 9 days had a persistent suppressive effect on urinary nitrogen excretion and respiratory quotient in both groups but caused a maintained elevation of the plasma FFA level only in the ad libitum group. 14C-Tripalmitin oxidation and oxygen consumption rates were unaffected by growth hormone.

Sign in / Sign up

Export Citation Format

Share Document