The distributions and morphological characteristics of neurons displaying immunoreactivity to the catecholamine synthetic enzymes, tyrosine hydroxylase[TH], dopamine-beta-hydroxylase[DBH], and phenyletha-nolamine-N-methyltransferase[PNMT] were examined in the adjacent sections of the diencephalon of the striped field mouse [Apodemus agrarius coreae].Only TH-, and no DBH- or PNMT-immunoreactive neurons were found in the diencephalon. In the preoptic area, TH-immunoreactive neurons were found in the anterior preoptic nucleus of Loo[APN], periventricular preoptic nucleus, medial preoptic nucleus, lateral preoptic nucleus and suprachiasmatic nucleus. In the hypothalamus, TH-immunoreactive neurons were found in theparaventricular hypothalamic nucleus, periventricular gray, retrochiasmatic area,anterior hypothalamic nucleus of anterior hypothalamic area and retrochiasmatic region of the hypothalamus. In the rostral tuberal region of the hypothalamus, TH-immunoreactive neurons were found in the paraventricular nucleus, periventricular gray and arcuate nucleus. In the midtuberal region of the hypothalamus, TH-immunoreactive neurons were found in the paraventricular nucleus, dorsomedial hypothalamic nucleus, zona incerta and arcuate nucleus. In the caudal tuberal region of the hypothalamus, dorsal hypothalamic nucleus, posterior hypothalamic complex and arcuate nucleus.
Animals ; Anterior Hypothalamic Nucleus ; Arcuate Nucleus ; Diencephalon* ; Dopaminergic Neurons* ; Dorsomedial Hypothalamic Nucleus ; Hypothalamus ; Immunohistochemistry ; Mice ; Neurons ; Paraventricular Hypothalamic Nucleus ; Preoptic Area ; Subthalamus ; Suprachiasmatic Nucleus ; Tyrosine

The presence and coexistence of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-diaphorase) with tyrosine hydroxylase (TH) was investigated by combining NADPH-diaphorase histochemistry with TH immunohistochemistry in hypothalamic nuclei of the rat. TH-immunoreactive and NADPH-diaphorase positive neurons were found in the medial preoptic area and medial preoptic nucleus, anterior hypothalamic area, dorsomedial hypothalamic nucleus, paraventricular nucleus, supraoptic nucleus and posterior hypothalamic area, respectively. TH and NADPH-diaphorase did not coexist in the anterior hypothalamic area, dorsomedial hypothalamic nucleus, medial preoptic area and posterior hypothalamic area. A considerable portion (30~50%) of the NADPH-diaphorase positive neurons in the supraoptic nucleus colocalized TH. In the medial preoptic area and paraventricular nucleus, some (5~15%) of TH-immunoreactive neurons also contained NADPH-diaphorase activity. NADPH-diaphorase is known to be an indicator of the enzyme nitric oxide synthase; these results therefore suggest that nitric oxide may play an important role in the regulation of the activity of the hypothalamic dopaminergic system of the rat.
Animals ; Anterior Hypothalamic Nucleus ; Dorsomedial Hypothalamic Nucleus ; Hypothalamus ; Immunohistochemistry ; NAD* ; Neurons* ; Niacinamide* ; Nitric Oxide ; Nitric Oxide Synthase ; Paraventricular Hypothalamic Nucleus ; Preoptic Area ; Rats* ; Supraoptic Nucleus ; Tyrosine 3-Monooxygenase* ; Tyrosine*

Widespread brain-derived neurotrophic factor (BDNF) mRNA and protein expression has been detected in the brain. Despite substantial overlap between BDNF mRNA and protein expression, there is general anatomical regions, where there is discordance of these expression. We performed, therefore, immunohistochemistry after colchicine treatment into the ventricle to evaluate the possible presence of BDNF-immunoreactive (IR) in the regions where BDNF mRNA was expressed, but not BDNF-IR. The results obtained were as follows; There was substantial increase in the number of BDNF-IR neurons in the anterior olfactory nucleus, the piriform cortex, the cerebral cortex, the claustrum, the stratum pyramidale of the CA2 and the CA3, the granule cell layer of the dentate gyrus, the basolateral amygdaloid nucleus, the lateral geniculate nucleus, the anteromedial thalamic nucleus, the anterodorsal thalamic nucleus, the paraventricular thalamic nucleus, the paraventricular hypothalamic nucleus and the ventromedial hypothalamus nucleus, compared to the same brain area of non-colchicine treated rat. We detected many new BDNF-IR neurons in the stratum pyramidale of the CA1, A1, A2, A4-A10 cell groups, C1-C3 cell groups, the raphe magnus nucleus, the lateral paragigantocellular nucleus and the spinal vestibular nucleus. The results show that the localization of BDNF-IR neurons after colchicine treatment is consistant with that of BDNF mRNA containing neurons in the brain.
Animals ; Anterior Thalamic Nuclei ; Basal Ganglia ; Brain* ; Brain-Derived Neurotrophic Factor ; Cerebral Cortex ; Colchicine* ; Dentate Gyrus ; Hypothalamus ; Immunohistochemistry ; Midline Thalamic Nuclei ; Neurons* ; Paraventricular Hypothalamic Nucleus ; Rats* ; RNA, Messenger

A current hypothesis of sleep-wake regulation proposes that the sleep process starts with the activation of sleep-promoting neurons located in the preoptic area of the anterior hypothalamus. This activation leads to the inhibition of wake-promoting neurons located in the posterior hypothalamus, basal forebrain, and mesopontine tegmentum, which, in turn removes inhibition from the sleep-promoting structures(i.e., disinhibition) to initiate the sleep process. Mutual inhibition between these wake- and sleep-promoting neurons results in switching properties that define discrete wakeful and sleep states with sharp transitions between them. Wake-promoting nuclei include the orexinergic lateral hypothalamic/perifornical area, the histaminergic tuberomammillary nucleus, the cholinergic pedunculopontine tegmental nucleus, the noradrenergic locus coeruleus, the 5-hydroxytryptaminergic raphe nuclei, and possibly the dopaminergic ventral tegmental area. The major sleep-promoting nucleus is the GABAergic ventrolateral preoptic nucleus of the hypothalamus. The regulation of sleep is classically viewed as the dual interaction of circadian(SCN-based) and homeostatic processes, and the propensity to be asleep or awake at any given time is a consequence of a sleep debt and its interaction with signals from the SCN circadian clock. To better understand the mechanisms of sleep and wakefulness, the focus of pharmacotherapy is on targeting specific therapies to the particular defect in sleep-wake regulation.
Circadian Clocks ; Circadian Rhythm ; Drug Therapy* ; Hypothalamic Area, Lateral ; Hypothalamus ; Hypothalamus, Anterior ; Hypothalamus, Posterior ; Locus Coeruleus ; Neuroanatomy* ; Neurons ; Pedunculopontine Tegmental Nucleus ; Preoptic Area ; Prosencephalon ; Raphe Nuclei ; Sleep Wake Disorders ; Ventral Tegmental Area ; Wakefulness

The role of neuropeptides in the central nervous system (CNS) has received increasing attention. Numerous peptide molecules are found in the mammalian CNS and many of them are thought to act as either neurotransmitters or neuromodulators. The neuropeptides found in high concentration in the hypothalamus include vasopressin (VP), vasoactive intestinal polypeptide, somatostatin, and oxytocin. The main approches to assess the involvement of neuropeptides can be focused on functions affecting the aging of the brain. Morphological aging of the CNS has been characterized by degenerative changes of fiber connections and cell loss, although degeneration does not always occur to the same extent throughout various parts of the brain and, moreover, varies for different cell types. Despite of many studies in VP containing neurons , there exist discrepancies in results about the changes of aged rat brain. The aim of the present study is, therefore, to investigative possible changes in the number and morphology of VPimmunoreactive neurons with aging in each area of the hypothalmus of the aged rats. As a result, the number of VP-immunoreactive neurons was decreased in hypothalamus nucleus of aged group. Especially, in VP-immunoreactive neurons of hypothalamus, the size of neuronal cell body and nuclei in aged group is larger than in young group and the fiber density of immunoreactivity neurons of median eminance (ME) in aged group is stronger than in young group. But, the total number of VP-immunoreactive neurons in the suprachiasmatic nucleus (SCN) of the aged group is larger than in the young group. These studies indicate the involvement of VP-immunoreactive neurons in aging process of hypothalamus, and aging process may affect the synthesis of VP in the neurons of hypothalamic nuclei. Whereas, in VP expression, aging process induces an enlargement of the cell size of surviving neurons to compensate.
Aging ; Animals ; Brain ; Cell Size ; Central Nervous System ; Hypothalamus* ; Neurons* ; Neuropeptides ; Neurotransmitter Agents ; Oxytocin ; Paraventricular Hypothalamic Nucleus ; Rats* ; Somatostatin ; Suprachiasmatic Nucleus ; Supraoptic Nucleus ; Vasoactive Intestinal Peptide ; Vasopressins

Bartha strain of pseudorabies virus[PRV-Ba] was utilized as a tracer to identify the neuronal axis of rat tongue muscles ; intrinsic muscles and extrinsic muscles, styloglossus, genioglossus, and hyoglossus muscle. After injection of 10 microliter of PRV-Ba into tongue muscles and 48-96 hours survivals, rats were perfused with 4% paraformaldehyde lysine periodate and brains were removed. PRV-Ba were localized in neural circuits by immunohistochemistry employing rabbit anti PRV-Ba as a primary antibody and ABC method. Injection of PRV-Ba into the tongue muscles resulted in uptake and retrograde transport of PRV-Ba in the rat brain. The result showed a circuit specific connection of many nerve cell groups along the time sequence : PRV-Ba immunoreactive cells appeared in hypoglossal nucleus and motor trigeminal nucleus ipsilaterally as seen with conventional tracers. Raphe nucleus, prepositus hypoglossal nucleus, spinal trigeminal nucleus, Al, A5 and facial nucleus of rhombencephalon showed immunoreactivity bilaterally. There were positive neurons in parabrachial nucleus, locus ceruleus, mesencephalic trigeminal nucleus, periaqueductal gray and A7 of mesencephalon and paraventricular nucleus, suprachiasmatic nucleus, organum vasculosum of lamina terminalis of diencephalon. Also positive reactions were showed in amygdala, insular cortex, frontal cortex and subfornical organ in telencephalon. Early immunoreactivity was appeared in hypoglossal nucleus and motor trigeminal nucleus, and there were positive neurons in the nuclei of the medulla oblongate, midbrain, pons, hypothalamus, cerebellum and medial preoptic area at middle stage. Subsequently the viral antigens were found in forebrain cell groups, paraventricular nuclei, suprachiasmatic nucleus, lateral hypothalamic area and primary motor cortex in frontal lobe bilaterally at 80-90hrs postinjection. These data demonstrate that the PRV-Ba can across synapses in the central nervous system with projection specific pattern, and this virus defines many elements of the neural network governing tongue. Therefore PRV-Ba are proved as a excellent neurotracer in the tract-tracing researches.
Amygdala ; Animals ; Antigens, Viral ; Axis, Cervical Vertebra ; Brain ; Central Nervous System ; Cerebellum ; Diencephalon ; Frontal Lobe ; Hypothalamic Area, Lateral ; Hypothalamus ; Immunohistochemistry ; Locus Coeruleus ; Lysine ; Mesencephalon ; Motor Cortex ; Muscles ; Neural Pathways* ; Neurons ; Paraventricular Hypothalamic Nucleus ; Periaqueductal Gray ; Pons ; Preoptic Area ; Prosencephalon ; Pseudorabies ; Raphe Nuclei ; Rats* ; Rhombencephalon ; Subfornical Organ ; Suprachiasmatic Nucleus ; Synapses ; Telencephalon ; Tongue* ; Trigeminal Nuclei ; Trigeminal Nucleus, Spinal

The preoptic area and anterior hypothalamus plays a pivotal role in body temperature regulation, and damage in this region causes hyperthermia. This hyperthermia is particularly troublesome because of the possibility that it may reflect an occult infectious process. We report a case of fever of unknown origin in a patient after removal of neoplasm involving the hypothalamus. A 29-year old man underwent craniotomy and removal of hypothalamic choroid meningioma. Seventy days after the removal of his tumor, his body temperature began to rise. But, there was no evidence of infection, inflammatory disease, metabolic disease, drug fever and recurred tumor. Repeated administration of antipyretic agent did not reduce body temperature. So, we considered that the elevated temperature had a central basis. The patient was treated with chlorpromazine in an attempt to lower his temperature. This drug reduced successfully his body temperature.
Adult ; Body Temperature ; Body Temperature Regulation ; Chlorpromazine ; Choroid ; Craniotomy ; Fever of Unknown Origin* ; Fever* ; Humans ; Hypothalamic Neoplasms* ; Hypothalamus ; Hypothalamus, Anterior ; Meningioma ; Metabolic Diseases ; Preoptic Area

As a consequence of the Earth's rotation, almost all organisms experience day and night cycles within a 24-hr period. To adapt and synchronize biological rhythms to external daily cycles, organisms have evolved an internal time-keeping system. In mammals, the master circadian pacemaker residing in the suprachiasmatic nucleus (SCN) of the anterior hypothalamus generates circadian rhythmicity and orchestrates numerous subsidiary local clocks in other regions of the brain and peripheral tissues. Regardless of their locations, these circadian clocks are cell-autonomous and self-sustainable, implicating rhythmic oscillations in a variety of biochemical and metabolic processes. A group of core clock genes provides interlocking molecular feedback loops that drive the circadian rhythm even at the single-cell level. In addition to the core transcription/translation feedback loops, post-translational modifications also contribute to the fine regulation of molecular circadian clocks. In this article, we briefly review the molecular mechanisms and post-translational modifications of mammalian circadian clock regulation. We also discuss the organization of and communication between central and peripheral circadian oscillators of the mammalian circadian clock.
Brain ; Circadian Clocks ; Circadian Rhythm ; Hypothalamus, Anterior ; Mammals ; Protein Processing, Post-Translational ; Suprachiasmatic Nucleus

Plasma levels of growth hormone(GH), luteinizing hormone(LH) and cortisol were determined by radioimmunoassay following radiofrequency(RF) stimulation or coagulation of various nuclei in thalamus and hypothalamus. RF stimulation or coagulation of many nuclei in thalamus and hypothalamus consisted of pulvinar and dorsomedial nucleus in thalamus and anterior and posterior hypothalamic nuclei in hypothalamus. Anterior thalamic stimulation resulted in highly significant increase of plasma LH, GH, cortisol and TH levels. However thalamic stimulation resulted no change in the level of various plasma hormones. Hypothalamic lesion produced significantly decreased plasma LH, GH and cortisol levels. Plasma cortisol and LH levels were highest 2 hours after stimulation while GH levels did not increased until 6 hours and TH until 72 hours respectively after stimulation. The significant difference in latency for beginning of hormone secretion suggests that GH, cortisol and LH may be controlled by several separate neuronal networks. Plasma GH and cortisol levels were lowest 72 hrs after coagulation of the anterior hypothalamic area, while GH, cortisol and LH levels did not change following stimulation or coagulation of posterior hypothalamic nucleus and thalamic nucldi. It was also noted that the anterior hypothalamic stimulation or coagulation caused increased or decreased in GH, cortisol, and LH than that observed from stimulation or coagulation of other hypothalamic and thalamic nuclei respectively.
Anterior Hypothalamic Nucleus ; Hydrocortisone ; Hypothalamus* ; Lutein ; Mediodorsal Thalamic Nucleus ; Neurons ; Plasma ; Pulvinar ; Radioimmunoassay ; Thalamic Nuclei ; Thalamus*

AIMTo investigate the possible central mechanism of antipyretic effects of Chinese medicine gypsum.

METHODSGypsum was injected after the fever model was established. The firing rate of thermosensitive neurons in preoptic-anterior hypothalamus(PO/AH) region was recorded by using extracellular microelectrode technique.

RESULTSThe injection of pyrogen evoked decrease in firing rate of the warm-sensitive neurons and increase in the cold-sensitive neurons in the region of PO/AH; the changes of the firing rate of pyrogen- treated warm-sensitive and cold-sensitive neurons could be reversed by the injection of gypsum.

CONCLUSIONThe result may suggest that antipyretic action of gypsum is mediated by its influences on the thermosensitivity neurons in the region of PO/AH.

Action Potentials ; Animals ; Antipyretics ; pharmacology ; Calcium Sulfate ; pharmacology ; Cats ; Fever ; physiopathology ; Hypothalamus, Anterior ; physiopathology ; Male ; Materia Medica ; pharmacology ; Neurons ; physiology ; Preoptic Area ; physiopathology ; Pyrogens