The spontaneously hypertensive rat (SHR) replicates many clinically relevant features of human essential hypertension and also exhibits behavioral symptoms of attention-deficit/hyperactivity disorder and dementia. The SHR phenotype is highly complex and cannot be explained by a single genetic or physiological mechanism. Nevertheless, numerous studies including our own work have revealed strikin...

BACKGROUND One underexploited property of anesthetics is their ability to probe neuronal regulation of arousal. At appropriate doses, anesthetics reversibly obtund conscious perception. However, individual anesthetic agents may accomplish this by altering the function of distinct neuronal populations. Previously the authors showed that isoflurane and sevoflurane inhibit orexinergic neurons, del...

A report by Payzan-LeNestour et al. (2013) in this issue of Neuron shows that the human locus coeruleus, a brain stem nucleus containing cell bodies of noradrenergic neurons, dynamically tracks the level of uncertainty about knowledge of the environment while making decisions.

The ability of grafted fetal ventral mesencephalic dopaminergic (DAergic) neuroblasts to reinnervate the unilaterally DA denervated rat striatum and improve motoric asymmetry has been well documented in several laboratories. The importance of host target specificity, and catecholamine (CA) neurotransmitter species, in the ability of grafts to ameliorate rotational responses to apomorphine and t...

a -Adrenoceptors are supposed to be important regulatory elements in responses to stress. Previous receptor binding studies in male 2 tree shrews have shown that chronic psychosocial stress down-regulates binding sites for a -adrenergic ligands in several brain stem 2 nuclei. The aim of the present study was to quantify effects of chronic subordination stress on expression of the a -adrenocepto...

Eyelid opening stretches mechanoreceptors in the supratarsal Müller muscle to activate the proprioceptive fiber supplied by the trigeminal mesencephalic nucleus. This proprioception induces reflex contractions of the slow-twitch fibers in the levator palpebrae superioris and frontalis muscles to sustain eyelid and eyebrow positions against gravity. The cell bodies of the trigeminal propriocepti...

Post-mortem and neuroimaging studies in Parkinson's disease (PD) have shown involvement of the brain serotoninergic, noradrenergic and cholinergic pathways alongside the characteristic degeneration of nigrostriatal dopamine neurons. The rate of progression of the degenerative process in these extrastriatal areas is still unclear. We used (18)F-dopa PET, a marker of aromatic aminoacid decarboxyl...

The locus coeruleus–noradrenergic system exerts an activating influence on forebrain neuronal and behavioral activity states. For example, in the anesthetized rat, unilateral locus coeruleus stimulation elicits bilateral activation of forebrain electroencephalographic activity. Pretreatment with a noradrenergic b-antagonist blocks this effect, suggesting that b-receptors play a critical role in...

STUDY OBJECTIVES We investigated the role of dopamine (DA) in behavioral state control and, in particular, paradoxical (or rapid eye movement) sleep (PS) generation in mesopontine structures. DESIGN Reverse microdialysis and polygraphic recordings in freely moving cats were used to assess the effects on sleep-wake states of applied DA and monoaminergic agonists and antagonists. SETTINGS NA....

The population of reserve alpha-2 adrenoceptors that mediate the inhibitory effect of clonidine on the activity of locus coeruleus neurons has been studied using extracellular recordings in anesthetized rats. Animals were pretreated with the irreversible receptor antagonist N-ethoxycarbonyl-2-ethoxy-1-2-dihydroquinoline (EEDQ). In rats pretreated with EEDQ (1, 2 and 6 mg/kg, i.p., 6 hr before e...