Increased sympathetic activity in rat white adipose tissue during prolonged fasting

1997 ◽  
Vol 272 (2) ◽  
pp. R656-R661 ◽  
Author(s):  
R. H. Migliorini ◽  
M. A. Garofalo ◽  
I. C. Kettelhut
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Sympathetic Activity ◽  
Epididymal Adipose Tissue ◽  
Turnover Rates ◽  
Prolonged Fasting ◽  
Interscapular Brown Adipose Tissue ◽  
Brown Adipose ◽  
6 Hydroxydopamine ◽  
Fasted Rats

The effect of prolonged fasting on sympathetic activity was examined in rat white adipose tissue (WAT) and, for comparison purposes, in interscapular brown adipose tissue (IBAT). Preliminary experiments showed that 6-hydroxydopamine or tyramine administration to fed animals produced similar reductions in norepinephrine (NE) content of WAT and IBAT. Fasting for 48 h did not affect tissue NE content significantly, but induced a threefold increase in [3H]NE uptake by retroperitoneal and epididymal adipose tissue, contrasting with a 50% reduction in IBAT. Measured with DL-alpha-methyl-p-tyrosine, NE fractional rates of turnover were faster and calculated turnover rates were three times higher in retroperitoneal and epididymal tissue from fasted rats than in tissues from fed controls. In experiments with [3H]NE, although fractional rates did not change significantly, calculated NE turnover also increased in retroperitoneal and epididymal tissue after food deprivation. In contrast, in IBAT, NE turnover either did not change (measured with DL-alpha-methyl-p-tyrosine) or, in the experiments with [3H]NE, decreased significantly after fasting. These and other data suggest that a centrally controlled selective activation of WAT sympathetic fibers contributes to fasting lipolysis.

Altered sympathetic activity during development of diet-induced obesity in rat

1983 ◽  
Vol 244 (3) ◽  
pp. R347-R355 ◽  
Author(s):  
B. E. Levin ◽  
J. Triscari ◽  
A. C. Sullivan
Keyword(s):  
Adipose Tissue ◽  
Lipid Content ◽  
Sympathetic Activity ◽  
Turnover Rates ◽  
Sprague Dawley ◽  
Interscapular Brown Adipose Tissue ◽  
Diet Induced Obesity ◽  
Brown Adipose ◽  
Obese Rats ◽  
Relative Body Weight

Sprague-Dawley rats developed diet-induced obesity (DIO) after 3 mo on a high-fat, high-sucrose diet (DIO diet), with associated increases in total body and interscapular brown adipose tissue (IBAT) lipid content. After 7 days on the DIO diet, rats had increased levels of tyrosine hydroxylase (TH; 34%), norepinephrine (NE; 34%), and NE turnover (94%; estimated by alpha-methyl-p-tyrosine inhibition of TH) in their IBAT compared with chow-fed controls. After 3 mo on the DIO diet, NE levels and/or turnover were reduced by 27–50% in aortas, hearts, and pancreata in obese rats. While IBAT NE turnover was normal, TH inhibition failed to increase the lipid content of IBAT in obese rats as it did in controls, suggesting a postsynaptic defect in basal NE-stimulated lipolysis in this thermogenically active tissue. When obese rats were switched from the DIO diet to rat chow for 3 days, NE levels remained depressed in their hearts (25%) and aortas (14%) but were increased by 36–45% in IBAT, pancreata, and white adipose tissue. NE turnover rates and/or constants were increased by 37–110% in hearts, aortas, pancreata, and IBAT of these obese rats while there were increased IBAT TH (20%) and dopamine-beta-hydroxylase (87%) activities compared with chow-fed controls. Therefore, sympathetic activity varied markedly as a function of both dietary composition and relative body weight during the development of DIO.

Effects of sucrose, caffeine, and cola beverages on obesity, cold resistance, and adipose tissue cellularity

1983 ◽  
Vol 244 (4) ◽  
pp. R500-R507 ◽  
Author(s):  
L. J. Bukowiecki ◽  
J. Lupien ◽  
N. Follea ◽  
L. Jahjah
Keyword(s):  
Adipose Tissue ◽  
Weight Gain ◽  
Brown Adipose Tissue ◽  
White Adipose Tissue ◽  
Cold Resistance ◽  
Body Weight Gain ◽  
Caffeine Intake ◽  
Interscapular Brown Adipose Tissue ◽  
Brown Adipose ◽  
Triglyceride Content

Rats consuming Coca-Cola and Purina chow ad libitum increased their total energy intake by 50% without excess weight gain. Their resistance to cold was markedly improved. These phenomena were characterized by significant increases in interscapular brown adipose tissue weight (IBAT) (91%), cellularity (59%), triglyceride content (52%), protein content (94%), and cytochrome oxidase activity (167%). In contrast, Coca-Cola consumption did not significantly affect the cellularity or triglyceride content of parametrial white adipose tissue (PWAT), although it slightly augmented PWAT weight. The effects of Coca-Cola on cold resistance, IBAT cellularity, and composition were entirely reproduced by sucrose, but not caffeine, consumption. Although caffeine also increased IBAT cellularity and composition, it significantly decreased the rate of body weight gain, PWAT weight, and adipocyte size. Moreover, it markedly inhibited adipocyte proliferation in PWAT thereby mimicking the effects of exercise training and food restriction (Bukowiecki et al., Am. J. Physiol. 239 (Endocrinol. Metab. 2): E422-E429, 1980). It is concluded a) that sucrose and Coca-Cola consumption improve the resistance of rats to cold, most probably by increasing brown adipose tissue cellularity, and b) that moderate caffeine intake might be useful for inhibiting proliferative activity in white adipose tissue, thereby preventing obesity.

Recovery of function in sympathetic nerves of interscapular brown adipose tissue of rats treated with 6-hydroxydopamine

1984 ◽  
Vol 62 (10) ◽  
pp. 1327-1332 ◽  
Author(s):  
Florent Depocas ◽  
David O. Foster ◽  
Gloria Zaror-Behrens ◽  
Suzanne Lacelle ◽  
B. Nadeau
Keyword(s):  
Blood Flow ◽  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Recovery Of Function ◽  
Subcutaneous Administration ◽  
Acclimation Temperature ◽  
Noradrenaline Content ◽  
Interscapular Brown Adipose Tissue ◽  
Brown Adipose ◽  
6 Hydroxydopamine

Twenty-four hours after subcutaneous administration of 6-hydroxydopamine (6-OHDA) at a dose of 10 mg/kg body weight in warm-acclimated rats, noradrenaline (NA) content and dopamine β-hydroxylase (DBH) activity of interscapular brown adipose tissue (IBAT) were reduced to about 10 and 35% of control values. Corresponding values for cold-acclimated rats, similarly treated, were 12 and 32%. In both groups of animals, calorigenic function in IBAT assessed by measurement of the effect of cold exposure on rate of blood flow through the tissue was lost almost completely. Twenty-four hours after treatment of rats with various doses of 6-OHDA, calorigenesis in IBAT was directly related to residual NA. Measurements of noradrenaline content and DBH activity from 1 to 10 days after 6-OHDA and the increase in IBAT blood flow of cold-exposed animals from 1 to 7 days after 6-OHDA indicated marked differences in the extent to which each of these indicators of the integrity and function of sympathetic nerve endings recovered with time and with the acclimation temperature of the animals. Regeneration of macromolecuiar components of noradrenergic vesicles in IBAT appeared to occur more rapidly in cold than in warm-acclimated animals. Thus, moderate doses of 6-OHDA may acutely sympathectomize IBAT, but as previously reported for other tissues, full recovery of function of IBAT occurs long before noradrenaline stores are replenished.

scholarly journals Effects of high-carbohydrate diets on lipogenesis in rat interscapular brown adipose tissue

1982 ◽  
Vol 206 (3) ◽  
pp. 667-669 ◽  
Author(s):  
P. John Weaire ◽  
Tazeen F. Kanagasabai
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
White Adipose Tissue ◽  
White Bread ◽  
Lipogenic Enzymes ◽  
Adipose Tissues ◽  
Interscapular Brown Adipose Tissue ◽  
High Carbohydrate ◽  
Brown Adipose

Cycloplasmic preparations from brown and white adipose tissues were assayed for three lipogenic enzymes throughout a programme of starvation followed by refeeding on either a normal or a white-bread diet. In the brown adipose tissue of rats fed on a white-bread diet the three enzymes were elevated to levels significantly higher than those in white adipose tissue.

scholarly journals Changes in the lipogenic response to feeding of liver, white adipose tissue and brown adipose tissue during the development of obesity in the gold-thioglucose-injected mouse

1989 ◽  
Vol 259 (3) ◽  
pp. 651-657 ◽  
Author(s):  
G J Cooney ◽  
M A Vanner ◽  
J L Nicks ◽  
P F Williams ◽  
I D Caterson
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
White Adipose Tissue ◽  
Liver Lipid ◽  
Insulin Concentration ◽  
Obese Mice ◽  
Interscapular Brown Adipose Tissue ◽  
Gold Thioglucose ◽  
Brown Adipose

Lipogenic response to feeding was measured in vivo in liver, epididymal white adipose tissue (WAT) and interscapular brown adipose tissue (BAT), during the development of obesity in gold-thioglucose (GTG)-injected mice. The fatty acid synthesis after a meal was higher in all tissues of GTG-treated mice on a total-tissue basis, but the magnitude of this increase varied, depending on the tissue and the time after the initiation of obesity. Lipogenesis in BAT from GTG mice was double that of control mice for the first 2 weeks, but subsequently decreased to near control values. In WAT, lipogenesis after feeding was highest 2-4 weeks after GTG injection, and in liver, lipid synthesis in fed obese mice was greatest at 7-12 weeks after the induction of obesity. The post-prandial insulin concentration was increased after 2 weeks of obesity, and serum glucose concentration was higher in fed obese mice after 4 weeks. These results indicate that increased lipogenesis in GTG-injected mice may be due to an increase in insulin concentration after feeding and that insulin resistance (assessed by lipogenic response to insulin release) is apparent in BAT before WAT and liver.

Dopamine β-hydroxylase and cytochrome oxidase activities in brown adipose tissue of newborn rats following sympathectomy with 6-hydroxydopamine

1977 ◽  
Vol 55 (3) ◽  
pp. 695-699 ◽  
Author(s):  
W. A. Behrens ◽  
Florent Depocas
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Cytochrome Oxidase ◽  
Newborn Rat ◽  
Interscapular Brown Adipose Tissue ◽  
Nervous System Activity ◽  
Brown Adipose ◽  
Rate Of Increase ◽  
6 Hydroxydopamine

Dopamine-β-hydroxylase (DBH) (EC 1.14.17.1) activity is present in the interscapular brown adipose tissue (IBAT) as early as 2 days of age in the white rat. The specific and the total activities of this enzyme, as well as those of cytochrome oxidase (COX) (EC 1.9.3.1) in IBAT increase up to at least 20 days of age. Daily administration of 6-hydroxydopamine (6-OHDA) between the second and the twelfth day after birth does not significantly alter IBAT weight gain relative to untreated controls, but the increase in protein content with age is reduced to about half the normal value at the end of the treatment. The treatment with 6-OHDA also results in a drastic lowering of DBH specific and total activities, and a much smaller rate of increase of COX specific and total activities with age in IBAT compared with controls. These results provide additional evidence for a previously proposed role of sympathetic nervous system activity in the development of the thermogenic potential of IBAT in the newborn rat.

Effects of 2-deoxy-D-glucose on sympathetic nerve activity to interscapular brown adipose tissue

1989 ◽  
Vol 257 (6) ◽  
pp. R1377-R1385 ◽  
Author(s):  
M. Egawa ◽  
H. Yoshimatsu ◽  
G. A. Bray
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Sympathetic Activity ◽  
Suppressive Effect ◽  
Cerebral Ventricle ◽  
Neural Activation ◽  
Central Administration ◽  
Interscapular Brown Adipose Tissue ◽  
The Third ◽  
Brown Adipose

The effects on firing rate of sympathetic nerves to interscapular brown adipose tissue were measured after induction of intracellular glycopenia by peripheral or central administration of 2-deoxy-D-glucose (2-DG). Injection of 2-DG (250 mg/kg body wt) into the jugular vein rapidly suppressed the sympathetic activity, which declined 84% within 10 min after the injection. This suppression persisted for at least 40 min. Hyperglycemia did not affect the sympathetic activity but partially inhibited the suppressive effect of 2-DG injection. Acute vagotomy failed to block the suppressive effect of 2-DG. Injection of 2-DG (2.5 mg/rat) into the third cerebral ventricle suppressed the sympathetic activity. This suppression was followed by gradual recovery. Saline injection did not affect the sympathetic activity. We conclude that cellular glycopenia induced by injecting 2-DG peripherally or into the third cerebral ventricle suppresses the sympathetic activity to brown adipose tissue. The results are consistent with the hypothesis that an acute energy shortage decreases the thermogenesis in interscapular brown adipose tissue by suppressing sympathetic neural activation of this tissue.

Sign in / Sign up

Export Citation Format

Share Document