Rat hypothalamic noradrenaline levels following midbrain raphé nuclei lesions.
Electrolytic lesions of the median and dorsal raphé nuclei resulted in statistically significant reductions in rat hypothalamic noradrenaline which were observed 1 or 2 days after lesioning, while no changes were observed 7 or 14 days after lesioning. The short term (1-2 days) raphé nuclei lesions produced no changes in hypothalamic 5-hydroxytryptamine or a small reduction in 5-hydroxyindole acetic acid while the expected marked reductions were observed after 7 days. The reduction in hypothalamic noradrenaline observed after short term raphé nuclei lesions suggests the existence of a positive feedback loop between 5-hydroxytryptamine neurons and noradrenaline terminals in the hypothalamus.
D000818:Animals; D005246:Feedback; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism*; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D011903:Raphe Nuclei / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism; D014364:Tryptophan / Q000378:metabolism
D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D014364:Tryptophan; D009638:Norepinephrine