Serotonin-dependent cerebral activation: effects of methiothepin and other serotonergic antagonists.
In scopolamine-treated (5.0 mg/kg, s.c.) rats hippocampal rhythmical slow activity (RSA) and neocortical low voltage fast activity (LVFA) occur only in close correlation with head movements, spontaneous changes in posture, or locomotion (Type I behavior). Previous work indicates that such scopolamine-resistant RSA and LVFA are dependent on ascending serotonergic projections. A test of 9 serotonergic antagonists (methiothepin; ritanserin; ketanserin; pizotifen; mianserin; pirenperone; ICS-205-930; metoclopramide; methysergide) showed that methiothepin produces a partial reduction in RSA and LVFA in scopolamine-treated rats, while the other antagonists are completely inactive over a wide range of doses. It may be that serotonergic cerebral activation depends on both 5-HT1 and 5-HT2 receptors.
Watson
N V
NV
Psychology Department, University of British Columbia, Vancouver, Canada.
Hargreaves
E L
EL
Penava
D
D
Eckel
L A
LA
Vanderwolf
C H
CH
D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects*; D004566:Electrodes; D006220:Haloperidol / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects*; D008297:Male; D008719:Methiothepin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000502:physiology*; D012702:Serotonin Antagonists / Q000494:pharmacology*
D012702:Serotonin Antagonists; D012701:Serotonin; D008719:Methiothepin; D006220:Haloperidol