Human adipose tissue blood flow during prolonged exercise II

1978 ◽  
Vol 376 (1) ◽  
pp. 41-45 ◽  
Author(s):  
Jens B�low ◽  
Joop Madsen
1983 ◽  
Vol 245 (3) ◽  
pp. H447-H452 ◽  
Author(s):  
P. Hjemdahl ◽  
B. Linde

The effects of circulating norepinephrine (NE) and epinephrine (Epi) on vascular resistance in subcutaneous adipose tissue and the calf as well as on plasma glycerol, an indicator of lipolysis, were studied in healthy volunteers. Adipose tissue blood flow was determined by the local clearance of 99mTcO-4 or 133Xe. The two isotopes gave similar results. Calf blood flow was determined by venous occlusion plethysmography. Intravenous infusion of NE caused increases in systolic and diastolic blood pressures, adipose tissue and calf vascular resistances, and plasma glycerol and a decrease in plasma insulin and heart rate, all of which were significant when arterial plasma NE was elevated from 1.17 +/- 0.14 to 8.38 +/- 0.30 nM (n = 16). Epi reduced diastolic and mean arterial pressures and adipose tissue and calf vascular resistances and increased plasma glycerol without affecting systolic blood pressure or plasma insulin. An increase of arterial plasma Epi from 0.20 +/- 0.03 to 1.15 +/- 0.05 nM (n = 6) was sufficient to induce vasodilatation in adipose tissue and lipolysis. Human adipose tissue differs from canine adipose tissue inasmuch as Epi causes vasodilatation in humans (present results) but vasoconstriction in the dog (previous results), presumably due to a predominance of vascular beta 2-adrenoceptors in human and beta 1-adrenoceptors in canine adipose tissue. Furthermore, Epi is a considerably more potent lipolytic hormone than NE in humans but not in the dog. Our results indicate that both NE and Epi may influence human adipose tissue blood flow and lipolysis as circulating hormones.


Obesity ◽  
2009 ◽  
Vol 17 (4) ◽  
pp. 681-688 ◽  
Author(s):  
Patricia Perez-Matute ◽  
Matthew J. Neville ◽  
Garry D. Tan ◽  
Keith N. Frayn ◽  
Fredrik Karpe

1995 ◽  
Vol 269 (6) ◽  
pp. E1059-E1066 ◽  
Author(s):  
B. Stallknecht ◽  
L. Simonsen ◽  
J. Bulow ◽  
J. Vinten ◽  
H. Galbo

Trained humans (Tr) have a higher fat oxidation during submaximal physical work than sedentary humans (Sed). To investigate whether this reflects a higher adipose tissue lipolytic sensitivity to catecholamines, we infused epinephrine (0.3 nmol.kg-1.min-1) for 65 min in six athletes and six sedentary young men. Glycerol was measured in arterial blood, and intercellular glycerol concentrations in abdominal subcutaneous adipose tissue were measured by microdialysis. Adipose tissue blood flow was measured by 133Xe-washout technique. From these measurements adipose tissue lipolysis was calculated. During epinephrine infusion intercellular glycerol concentrations were lower, but adipose tissue blood flow was higher in trained compared with sedentary subjects (P < 0.05). Glycerol output from subcutaneous tissue (Tr: 604 +/- 322 nmol.100 g-1.min-1; Sed: 689 +/- 203; mean +/- SD) as well as arterial glycerol concentrations (Tr: 129 +/- 36 microM; Sed: 119 +/- 56) did not differ between groups. It is concluded that in intact subcutaneous adipose tissue epinephrine-stimulated blood flow is enhanced, whereas lipolytic sensitivity to epinephrine is the same in trained compared with untrained subjects.


1989 ◽  
Vol 257 (4) ◽  
pp. R711-R716 ◽  
Author(s):  
D. B. West ◽  
W. A. Prinz ◽  
M. R. Greenwood

Adipose tissue blood flow was measured in five depots, and plasma concentrations of glucose, insulin, and triglyceride were measured at 0, 15, 30, and 45 min after the start of a meal in unanesthetized, freely moving rats. In addition, adipose tissue lipoprotein lipase activity was measured in four depots before and 45 min after the start of a meal. Plasma glucose was significantly elevated only at the 15-min time point, and while plasma triglyceride increased these changes did not reach significance. Plasma insulin was significantly elevated at all time points after a meal. Feeding resulted in a consistent decrease of adipose tissue blood flow expressed per gram wet weight of tissue. This decrease was maximal at 30 min after the start of feeding. The decrease in adipose tissue blood flow averaged 45% at 45 min after the start of feeding for the five depots evaluated. Lipoprotein lipase activity significantly increased in the retroperitoneal and mesenteric fat depots at 45 min after the meal start, but did not change in the epididymal or dorsal subcutaneous fat depots. These results suggest that a decrease in adipose tissue blood flow is a normal result of a meal in the rat. The regional specificity of changes in adipose tissue lipoprotein lipase activity supports the concept of regional specificity of function for adipose tissue and suggests that the mesenteric and retroperitoneal depots are particularly important for the storage of triglycerides immediately after a meal.


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