Sleep central

Barbituric acid is the parent of a group of compounds known as barbiturates The bar biturates are classified as sedative-hypnotic agents meaning that they decrease the responsiveness of the central nervous system and promote sleep Thousands of deriva lives of the parent ring system of barbituric acid have been tested for sedative-hypnotic activity the most useful are the 5 5 disubstituted derivatives... 

Caffeine is considered by pharmacologists to be a mild stimulant of the central nervous system. It has been shown to promote feelings of well being and increased abiUty to perform certain mental tasks efficiently. There are people who are oversensitive to the effects of caffeine overindulgence by these individuals, eg, intake of more than 600 mg caffeine/d, can bring unwanted effects such as anxiety, restlessness, sleeping difficulties, headache, or palpitations of the heart (54). 

Sedative-hypnotic. A drug that decreases responsiveness of the central nervous system to the point of promoting sleep. 

Antidepressants Noradrenaline/5-HT transporters Na+, K+ channels l Noradrenaline/ 5-HT reuptake l Na+ currents t K+ currents l Excitability of peripheral and central neurons Cardiac arrhythmia, myocardial infarction, sedation, nausea, dry mouth, constipation, dizziness, sleep disturbance, blurred vision... 

The nervous system is a complex part of the human body concerned with die regulation and coordination of body activities such as movement, digestion of food, sleep, and elimination of waste products. The nervous system has two main divisions the central nervous system (CNS) and the peripheral nervous system (PNS). Figure 22-1 illustrates the divisions of die nervous system. 

Central nervous sysfe/n-dreamless sleep, drowsiness atropine may produce mild stimulation in some patients e-mydriasis (dilatation of the pupil), cydoplegia (paralysis of accommodation or inability to focus the eye)... 

All barbiturates have essentially die same mode of action. Depending on the dose given, tiiese drags are capable of producing central nervous system (CNS) depression and mood alteration ranging from mild excitation to mild sedation, hypnosis (sleep), and deep coma These drugs also are respiratory depressants the degree of depression... 

Wise MG, Fisher JG, de la Pena AM. 1983. Trichloroethane (TCE) and central sleep apnea a case study. 

Although histamine has mixed excitatory and inhibitory effects on central neurons, those antihistamines (Hi-receptor antagonists) that enter the brain produce sedation this indicates that the predominant overall effect of histamine is excitatory. The preferred explanation for this rests on evidence that histaminergic neurons in the posterior hypothalamus are active in waking and silent in deep SWS and REM sleep. 

Hypnotics induce states of drowsiness and facilitate the onset and continuation of sleep resembling natural sleep [32]. Central nervous system (CNS) functions, in addition to the maintenance of wakefulness, are usually depressed by these drugs. Barbiturates, clinically... 

Although most of the medicinal chemistry effort in the H3 receptor field has been focused on the development of antagonists, there is some interest in agonists as well. Histamine H3 receptor agonists decrease the release of histamine in the central and peripheral nervous system and lead to a weakened histaminergic tone. In the brain, their effects will therefore be comparable to those of Hi receptor antagonists, with sedation and induction of sleep as a prominent observation. Indeed, H3 agonists such as the imidazoles... 

Complicated processes govern wakefulness, sleep, and the transitions leading to sleep initiation and maintenance. Although the neurophysiology of sleep is complex, certain neurotransmitters promote sleep and wakefulness in different areas of the central nervous system (CNS). Serotonin is thought to control non-REM sleep, whereas cholinergic and adrenergic transmitters mediate REM sleep. Dopamine, norepinephrine, hypocretin, substance P, and histamine all play a role in wakefulness. Perturbations of various neurotransmitters are responsible for some sleep disorders and explain why various treatment modalities are beneficial. 

Hydroxy tryptamine, or serotonin, is a neurotransmitter in the central nervous system (CNS). The nerve-cell bodies of the major serotoninergic neurones are in the midline raphe nuclei of the rostral pons, and ascending fibers innervate the basal ganglia, hypothalamus, thalamus, hippocampus, limbic forebrain, and areas of the cerebral cortex. The serotoninergic system plays an important role in the control of mood and behavior, motor activity, hunger, thermoregulation, sleep, certain hallucinatory states, and some neuro-endocrine mechanisms. 

The concept of chemical neurotransmission originated in the 1920s with the classic experiments of Otto Loewi (which were themselves inspired by a dream), who demonstrated that by transferring the ventricular fluid of a stimulated frog heart onto an unstimulated frog heart he could reproduce the effects of a (parasympathetic) nerve stimulus on the unstimulated heart (Loewi Navratil, 1926). Subsequently, it was found that acetylcholine was the neurotransmitter released from these parasympathetic nerve fibers. As well as playing a critical role in synaptic transmission in the autonomic nervous system and at vertebrate neuromuscular junctions (Dale, 1935), acetylcholine plays a central role in the control of wakefulness and REM sleep. Some have even gone as far as to call acetylcholine a neurotransmitter correlate of consciousness (Perry et al., 1999). 

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