Effects of electrical stimulation of the dorsal raphe nucleus on local cerebral blood flow in the rat.
We have studied the effects of electrical stimulation of the dorsal raphe nucleus on local cerebral blood flow (LCBF), as assessed by the quantitative [14C]-iodoantipyrine autoradiographic technique. Stimulation of the dorsal raphe nucleus in the alpha-chloralose anesthetized rat caused a significant decrease in LCBF, ranging from -13 to -26% in 24 brain structures out of 33 investigated. The most pronounced decreases (-23 to -26%) were observed in the accumbens, amygdaloid, interpeduncular nuclei and in the median raphe nucleus, limbic system relays. The decreases also concerned cortical regions and the extrapyramidal system. These results indicate that activation of ascending serotonergic system produces a vasoconstriction and that the dorsal raphe nucleus has a widespread modulatory influence on the cerebral circulation.
Bonvento
G
G
Laboratoire de Physiologie et Physiopathologie Cérébrovasculaire, INSERM CNRS, Université Paris VII, France.
Lacombe
P
P
Seylaz
J
J
D000818:Animals; D000983:Antipyrine / Q000031:analogs & derivatives; D001345:Autoradiography; D002250:Carbon Radioisotopes; D002540:Cerebral Cortex / Q000098:blood supply; D002560:Cerebrovascular Circulation; D004558:Electric Stimulation; D008032:Limbic System / Q000098:blood supply; D008297:Male; D011903:Raphe Nuclei / Q000098:blood supply / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000502:physiology; D014661:Vasoconstriction
D002250:Carbon Radioisotopes; D012701:Serotonin; D000983:Antipyrine; C008135:iodoantipyrine