Immunoneutralization of melanin-concentrating hormone (MCH) in the dorsal raphe nucleus: effects on sleep and wakefulness.
Summary of "Immunoneutralization of melanin-concentrating hormone (MCH) in the dorsal raphe nucleus: effects on sleep and wakefulness."
Hypothalamic neurons that utilize melanin-concentrating hormone (MCH) as a neuromodulator exert a positive control over energy homeostasis, inducing feeding and decreasing metabolism. Recent studies have shown also that this system plays a role in the generation and/or maintenance of sleep. MCHergic neurons project to the serotonergic dorsal raphe nucleus (DR), a neuroanatomical structure involved in several functions during wakefulness (W), and in the regulation of rapid-eye movements (REM) sleep. Recently, we determined the effect of MCH microinjected into the DR on sleep variables in the rat. MCH produced a marked increment of REM sleep, whereas slow wave sleep (SWS) showed only a moderate increase. In the present study, we analyze the effect of immunoneutralization of MCH in the DR on sleep and W in the rat. Compared to the control solution, microinjections of anti-MCH antibodies (1/100 solution in 0.2 μl) induced a significant increase in REM sleep latency (31.2±7.1 vs. 84.2±24.8 min, p<0.05) and a decrease of REM sleep time (37.8±5.4 vs. 17.8±2.9 min, p<0.05) that was related to the reduction in the number of REM sleep episodes. In addition, there was an increase of total W time (49.8±4.6 vs. 72.0±5.7 min, p<0.01). Light sleep and SWS remained unchanged. The intra-DR administration of a more diluted solution of anti-MCH antibodies (1/500) or rabbit pre-immune serum did not modify neither W nor REM sleep variables. Our findings strongly suggest that MCH released in the DR facilitates the occurrence of REM sleep.
Department of Physiology, School of Medicine, University of the Republic, Montevideo, Uruguay.
This article was published in the following journal.
Name: Brain research
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21078307
- DOI: http://dx.doi.org/10.1016/j.brainres.2010.11.027
Medical and Biotech [MESH] Definitions
Dorsomedial Hypothalamic Nucleus
An aggregation of cells in the middle hypothalamus dorsal to the ventromedial nucleus and bordering the third ventricle.
Collections of small neurons centrally scattered among many fibers from the level of the trochlear nucleus in the midbrain to the hypoglossal area in the medulla oblongata.
Anterior Thalamic Nuclei
Three nuclei located beneath the dorsal surface of the most rostral part of the thalamus. The group includes the anterodorsal nucleus, anteromedial nucleus, and anteroventral nucleus. All receive connections from the mamillary body and fornix, and project fibers to the cingulate body.
Neural nuclei situated in the septal region. They have afferent and cholinergic efferent connections with a variety of forebrain and brainstem areas including the hippocampus, the lateral hypothalamus, the tegmentum, and the amygdala. Included are the dorsal, lateral, medial, and triangular septal nuclei, septofimbrial nucleus, nucleus of diagonal band, nucleus of anterior commissure, and the nucleus of stria terminalis.
Lateral Thalamic Nuclei
A narrow strip of cell groups on the dorsomedial surface of the thalamus. It includes the lateral dorsal nucleus, lateral posterior nucleus, and the PULVINAR.
To examine the effects of bilateral microinjection of melanin-concentrating hormone (MCH) 50 and 100ng into the horizontal limb of the diagonal band of Broca (HDB) on sleep variables during the light...
The present study was designed to reveal the projection patterns of lateral hypothalamic (LH), cocaine- and amphetamine-regulated transcript (CART) neurons to the dorsal raphe (DR) and/or the locus co...
Melanin concentrating hormone (MCH) is an important mediator of energy homeostasis and plays role in several disorders such as obesity, stress, depression and anxiety. The synthesis and biological eva...
Altered brain serotonin activity is implicated in schizophrenia. We have previously shown differential involvement of serotonergic projections from the dorsal or median raphe nucleus in phencyclidine-...
C-type natriuretic peptide (CNP), the most abundant natriuretic peptide hormone in the brain, plays an important role in neuroendocrine function. The physiological effects of CNP are mediated by the n...
Drooping of nucleus is a common complication during cataract extraction by phacoemulsification. The investigators describe a new technique to retrieve the dropped nucleus by using an instr...
This study objectives are to compare the efficacy and safety between surgical excision and manual rupture for dorsal carpal ganglion.The participants with dorsal carpal ganglion will be ra...
The purpose of this study is to evaluate whether the Iowa/Nucleus 10/10 mm in one ear, in conjunction with a Nucleus Freedom implant in the other ear can provide useful binaural hearing in...
To evaluate the performance of the Nucleus 5 Cochlear Implant System.
The purpose of the study is to determine the optimal surgical approach (ventral versus dorsal) for patients with multi-level cervical spondylotic myelopathy (CSM). There are no establishe...