AIM To investigate the role of serotonergic projection from dorsal raphe nuclei (DRN) to basolateral amygadaloid (BLA) in the regulation of sleep and waking state. METHODS stereotaxic microinjection and polysomnography were employed. RESULTS Microinjection of L Glu into the DRN caused an enhancement of wake (W) and a decrease of slow wave sleep (SWS) and paradoxical sleep (PS). However, microinjection of L Glu into the DRN plus bilateral microinjection of methysergide (MS) into the BLA reversed the effects of L Glu. Microinjection of PCPA into the DRN caused an enhancement of SWS and a decrease of W. Microinjection of PCPA into the DRN plus bilateral microinjection of 5 HTP into the BLA reversed the effects of PCPA. CONCLUSION These results suggest that the role of the DRN in the regulation of sleep and waking state is partly mediated by serotonergic projection from the DRN to the BLA.

AIM To study the role of serot on in (5-HT) in ventrolateral preoptic nucleus(VLPO) on sleep and wakefulness cycl e of rat by microinjection of 5-hydroxytryptaphan (5-HTP , precursor of 5-HT ) , non-special 5-HT receptor antagonist methysergide (MS) and 5-HT retake i nhibitor fluoxetine. METHODS Stereotaxic, microinjection and po lysomnography (PSG) were used in the experiment. RESULTS There was no significant effect by microinjection of 5-HTP(0 5 ?g,0 1 ?l) into VLPO,but microinjection of 5-HTP(1 ?g,0 1 ?l)and fluoxetine lead wake i ncreased and sleep decreased; while microinjection of non-selective serotonin receptor antagonist MS lead to the opposited effect. The chang of sleep-wakefu lness cycle caused by 5-HTP or MS were significantly assiociated with time. CONCLUSION 5-HT involved in the regulation of sleep-wake cycle a nd promoted wake in the VLPO and its role of promotion may involve the gene exp ression of post-synaptic neurons.