Activation of brown adipose tissue thermogenesis by chemical stimulation of the posterior hypothalamus

Experiments were designed to determine in the same animal whether electrical stimulation of the posterior hypothalamus and ventromedial hypothalamic nucleus could specifically evoke shivering and nonshivering (brown adipose tissue) thermogenesis, respectively, in anesthetized, normothermic rats. Urethane-anesthetized, male Long–Evans rats, kept at 37 °C, had colonic (Tc), gastrocnemius muscle (Tm), intrascapular brown adipose tissue (TIBAT), and tail (Tt) temperatures measured via thermistor probes, and electromyogram activity (differential multiunit activity from bipolar recording electrodes within gastrocnemius muscle) recorded, before and after unilateral electrical stimulation (monophasic 0.5-ms pulses of 200 μA at 50 Hz for 30 s) of the posterior hypothalamus and ventromedial hypothalamic nucleus (via stereotaxically implanted concentric stimulating electrodes). Each rat showed shivering (increased electromyogram activity) following posterior hypothalamic stimulation, which caused an immediate rise in Tm values with no change in TIBAT or Tt values. Electrical stimulation of the ventromedial hypothalamic nucleus of the same animals elicited no shivering activity, but significant increases in TIBAT values occurred with no change in Tm or Tt values. Results confirm that stimulation of the posterior and ventromedial hypothalamic nuclei in rodents specifically activates shivering and nonshivering (brown adipose tissue) effector mechanisms, respectively, to raise core temperature.Key words: posterior hypothalamus, shivering thermogenesis, ventromedial hypothalamus, intrascapular brown adipose tissue thermogenesis.

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Dopaminergic Input from the Posterior Hypothalamus to the Raphe Pallidus Area Inhibits Brown Adipose Tissue Thermogenesis

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00149.2021 ◽

2021 ◽

Author(s):

Ellen Paula Santos da Conceição Furber ◽

Clarissa M.D. Mota ◽

Edward Veytsman ◽

Shaun F. Morrison ◽

Christopher J. Madden

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Posterior Hypothalamus ◽

Brown Adipose ◽

Premotor Neurons ◽

Brown Adipose Tissue Thermogenesis ◽

Pre Treatment ◽

Type 3 ◽

Raphe Pallidus

Systemic administration of dopamine (DA) receptor agonists leads to falls in body temperature. However, the central thermoregulatory pathways modulated by DA have not been fully elucidated. Here we identified a source and site of action contributing to DA's hypothermic action by inhibition of brown adipose tissue (BAT) thermogenesis. Nanoinjection of the type 2 and type 3 DA receptor (D2R/D3R) agonist, 7-OH-DPAT, in the rostral raphe pallidus area (rRPa) inhibits the sympathetic activation of BAT evoked by cold exposure or by direct activation of NMDA receptors in the rRPa. Blockade of D2R/D3R in the rRPa with nanoinjection of SB-277011A increases BAT thermogenesis, consistent with a tonic release of DA in the rRPa contributing to inhibition of BAT thermogenesis. Accordingly, D2R are expressed in cold-activated and serotonergic neurons in the rRPa and anatomical tracing studies revealed that neurons in the posterior hypothalamus (PH) are a source of dopaminergic input to the rRPa. Disinhibitory activation of PH neurons with nanoinjection of gabazine inhibits BAT thermogenesis, which is reduced by pre-treatment of the rRPa with SB-277011A. In conclusion, the rRPa, the site of sympathetic premotor neurons for BAT, receives a tonically-active, dopaminergic input from the PH that suppresses BAT thermogenesis.

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GDP binding to brown-adipose-tissue mitochondria of mice treated chronically with corticosterone

Biochemical Journal ◽

10.1042/bj2140265 ◽

1983 ◽

Vol 214 (1) ◽

pp. 265-268 ◽

Cited By ~ 44

Author(s):

K S Galpin ◽

R G Henderson ◽

W P T James ◽

P Trayhurn

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Cytochrome Oxidase ◽

Oxidase Activity ◽

Cytochrome Oxidase Activity ◽

Acute Response ◽

Brown Adipose ◽

Brown Adipose Tissue Thermogenesis ◽

Ad Libitum ◽

Stimulation Of

Cytochrome oxidase activity and mitochondrial GDP binding were decreased in brown adipose tissue of mice treated chronically with corticosterone. These changes occurred both in corticosterone-treated mice fed ad libitum and in treated mice pair-fed to control animals. Although the dietary stimulation of brown-adipose-tissue thermogenesis was suppressed by corticosterone, the acute response to cold was not affected.

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Brown adipose tissue thermogenesis is activated by electrical and chemical (l-glutamate) stimulation of the ventromedial hypothalamic nucleus in cold-acclimated rats

Brain Research ◽

10.1016/0006-8993(90)91579-6 ◽

1990 ◽

Vol 522 (1) ◽

pp. 76-82 ◽

Cited By ~ 22

Author(s):

I. Halvorson ◽

L. Gregor ◽

J.A. Thornhill

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Hypothalamic Nucleus ◽

Ventromedial Hypothalamic Nucleus ◽

Brown Adipose ◽

Brown Adipose Tissue Thermogenesis ◽

Stimulation Of

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Quantitative contribution of brown adipose tissue thermogenesis to overall metabolism

Canadian Journal of Biochemistry and Cell Biology ◽

10.1139/o84-082 ◽

1984 ◽

Vol 62 (7) ◽

pp. 618-622 ◽

Cited By ~ 65

Author(s):

David O. Foster

Keyword(s):

Blood Flow ◽

Adipose Tissue ◽

Brown Adipose Tissue ◽

Wild Mammals ◽

Brown Adipose ◽

Brown Adipose Tissue Thermogenesis ◽

Diet Induced Thermogenesis ◽

Quantitative Contribution ◽

Arteriovenous Difference ◽

Stimulation Of

Measurement of brown adipose tissue (BAT) blood flow coupled, when feasible, with measurement of the arteriovenous difference in oxygen across the tissue has been used to estimate the contribution of BAT thermogenesis to the metabolism of several species of laboratory, domestic, or wild mammals under various conditions: warm or cold exposure; arousal from hibernation; stimulation of metabolism by exogenous noradrenaline in warm- or cold-acclimated animals, in lean or obese animals, and in animals exhibiting high- or low-diet-induced thermogenesis. These studies have shown that in some species and under certain conditions BAT thermogenesis may account for as much as about one-third of the overall metabolic rate.

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Apparent dissociation between sympathetic activity and brown adipose tissue thermogenesis during pregnancy and lactation in golden hamsters

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y87-380 ◽

1987 ◽

Vol 65 (12) ◽

pp. 2396-2399 ◽

Cited By ~ 6

Author(s):

P. Trayhurn ◽

M. C. Wusteman

Keyword(s):

Adipose Tissue ◽

Brown Adipose Tissue ◽

Sympathetic Activity ◽

Noradrenaline Turnover ◽

Golden Hamsters ◽

Brown Adipose ◽

Brown Adipose Tissue Thermogenesis ◽

Pregnancy And Lactation ◽

Sympathetic Nervous ◽

Stimulation Of

Sympathetic activity has been assessed by measurements of noradrenaline turnover in brown adipose tissue and in the heart of golden hamsters during pregnancy and lactation. Noradrenaline turnover was not significantly altered in either tissue in pregnant or lactating hamsters, despite the atrophy of brown adipose tissue that occurs during reproduction. This suggests that sympathetic activity and brown adipose tissue thermogenesis are dissociated during pregnancy and lactation in golden hamsters. The results also indicate that the large increase in food intake during lactation does not lead to a diet-induced stimulation of the sympathetic nervous system.

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