Inhibitory effect of midbrain raphe stimulation on the maintenance of an active avoidance reflex.
Performance of an active avoidance (bench-jumping) reflex has been studied in rats during stimulation of the midbrain raphe nuclei. Raphe stimulation (10 cps, 0.2 msec, 2.5-5.0 V) inhibited the performance of the reflex. A serotonin receptor blocker (methysergide, 2.0 mg/kg IP) increased the reflex performance in non-stimulated animals and prevented the action of raphe stimulation. The data indicate that the cerebral serotoninergic system might have an inhibitory control over the performance of conditioned avoidance reflex.
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D003213:Conditioning, Psychological / Q000187:drug effects / Q000502:physiology; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D008297:Male; D008636:Mesencephalon / Q000502:physiology*; D008784:Methysergide / Q000494:pharmacology; D009434:Neural Pathways / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012018:Reflex; D013238:Stereotaxic Techniques
D008784:Methysergide