Rapid eye movement sleep in males is characterized by penile erection along with EEG desynchronization, muscle atonia, ponto-geniculo-occipital waves, and rapid eye movements (REM). The central neural mechanisms regulating sleep related erections (SREs) are not known. Recently, the lateral preoptic area has been shown to contribute in sleep-related erectile mechanisms. The present study was con...

Acetylcholinesterase (AchE) is a large glycoprotein that, aside from its known cholinolytic activity, co-exists with other transmitter systems and possesses other functions. In the present study, the effects of short-term rapid-eye-movement sleep deprivation (REM-SD) on AchE activity in the anterior hypothalamic area have been investigated. Using the flower-pot method, adult male albino ra...

Transdermal scopolamine has been widely used for the prevention of motion-sickness by travelers due to its potent anticholinergic effects and the ease of administration. Nevertheless, its effects on sleep physiology are not known, despite the wellknown fact that the administration of scopolamine as an injection or an oral form could influence the sleep architecture, especially prolonging rapid ...

The daily timing of rapid eye movement (REM) sleep reflects an interaction between the circadian pacemaker located in the suprachiasmatic nucleus of the hypothalamus (SCN) and a homeostatic process that induces compensatory REM sleep in response to REM sleep loss. Whether the circadian variation in REM sleep propensity is caused by active promotion, inhibition, or passive gating of REM sleep ho...

Sleep is characterized as rapid eye movement (REM) and non-rapid eye movement (NREM) sleep. Studies suggest that wake-related neurons in the basal forebrain, posterior hypothalamus and brainstem, and NREM sleep-related neurons in the anterior-hypothalamic area inhibit each other, thus alternating sleep-wakefulness. Similarly, pontine REM-ON and REM-OFF neurons reciprocally inhibit each other fo...

Most antidepressants suppress rapid eye movement (REM) sleep, which is thought to be important to brain function, yet the resulting REM sleep restriction is well tolerated. This study investigated the impact of antidepressants with different mechanisms of action, such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCA), on the regulation of REM sleep in rats. ...

In vivo microdialysis was used to analyze the role of dorsal raphe nucleus (DRN) neurons in regulating the sleep-waking cycle. Measurements of extracellular serotonin (5-HT) were made in the DRN of freely moving adult cats before and during microdialysis perfusion of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), a selective 5-HT1A receptor agonist, in artificial CSF. Behavioral state alte...

The response to inspiratory resistance loading (IRL) of the upper airway during sleep in children is not known. We, therefore, evaluated the arousal responses to IRL during sleep in children with the obstructive sleep apnea syndrome (OSAS) compared with controls. Children with OSAS aroused at a higher load than did controls (23 +/- 8 vs. 15 +/- 7 cmH(2)O. l(-1). s; P < 0.05). Patients with OSAS...

OBJECTIVES To examine whether disrupted regulation of REM sleep propensity is implicated in nightmare (NM) pathophysiology. BACKGROUND Heightened REM propensity induced by REM sleep deprivation is belied by increases in REM %, REM density and the dream-like quality of dream mentation during post-deprivation recovery sleep. Compromised regulation of REM sleep propensity may be a contributing f...