Relationship between hypothalamic noradrenergic activity and the sympathetic activity in interscapular brown adipose tissue after cold-swim stress in rats.
Noradrenaline (NA) activities in both hypothalamus and interscapular brown adipose tissue (IBAT) were simultaneously assessed before and after cold-swim stress in rats. The technique of gas chromatography-mass spectrometry was employed for the analysis of NA and its primary neuronal metabolite, 3,4-dehydroxy-phenylethylenglycol (DHPG), and the ratio of DHPG to NA was used as an index of NA activity. The ratios of DHPG/NA in both hypothalamus and IBAT were significantly elevated 5 and 20 min after cold-swim stress. Moreover, we found that there is a highly significant positive relationship between the hypothalamic DHPG/NA ratio and the ratio of DHPG/NA in IBAT (r = 0.872, p less than 0.0001). This observation strongly supports the concept in which hypothalamic NA neurons play an important role in modulating the sympathetic outflow.
Gotoh
M
M
Garvan Institute of Medical Research, St. Vincent's Hospital, Sydney, Australia.
Smythe
G A
GA
Iguchi
A
A
D002001:Adipose Tissue, Brown / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D003080:Cold Temperature; D007031:Hypothalamus / Q000378:metabolism / Q000502:physiology*; D008297:Male; D008734:Methoxyhydroxyphenylglycol / Q000031:analogs & derivatives / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012540:Scapula; D013312:Stress, Physiological / Q000209:etiology / Q000378:metabolism*; D013550:Swimming; D013564:Sympathetic Nervous System / Q000378:metabolism / Q000502:physiology*
D008734:Methoxyhydroxyphenylglycol; C010117:3,4-dihydroxyphenylglycol; D009638:Norepinephrine