(n.) The middle segment of the brain; the mesencephalon. See Brain.
Example Sentences:
(1) However, this inhibition was not found in rats treated with castor oil for 3 d. Moreover, 5-HT concentration in the midbrain significantly decreased in rats that acquired the adaptability for the occurrence of diarrhea.
(2) A train of conditioning stimuli to either of the midbrain nuclei produced inhibition of evoked population spikes recorded in the CA1 pyramidal cell layer of the hippocampus.
(3) Electrophysiological methods were used to determine changes in the neural representation of the binocular visual field at the paired midbrain optic tecta and in the tectal projection of pairs of corresponding retinal loci at various developmental points between these ages.
(4) Intracerebral injection of the GABAA agonists muscimol (1 nmol), isoguvacine (1 nmol) or THIP (1, 2 and 4 nmol) in rats with chemitrodes implanted in the dorsal midbrain central grey raised the threshold electrical current for inducing escape behaviour.
(5) Striking similarities were found between the functional pathways affected differentially by RET stimulation and well-defined cholinergic pathways which originate in the midbrain tegmentum.
(6) These responses were prominent in the rostral midbrain.
(7) Single neurons in the midbrain tegmentum of rats showed clear discriminatory responses to three tones announcing either food or water or no reinforcement.
(8) Stimulation using implanted electrodes in conscious rats, within the hypothalamic and midbrain areas described above, elicited typical 'flight' and 'escape' behaviour: thus, the localized regions from which the visceral alerting response is elicited contain neurones or nerve fibres integrating the whole defence-alerting response in the rat, as in other species.
(9) ruber, anterodorsolateral midbrain tegmentum, superior and inferior colliculi, pontine gray, cerebral peduncles, medial pontine reticular formation, raphe and vestibular nuclei did not affect the acoustic structure of the calls tested.
(10) This paper describes the distribution of histamine-like immunoreactivity in the midbrain and suboesophageal ganglion of the sphinx moth Manduca sexta.
(11) Parkinsonism in the present case may be due to the involvement of multiple neuronal circuits of the extrapyramidal system at the level of the midbrain to the thalamus.
(12) As a result the dipole of the wave V of auditory brainstem responses was found near the contralateral midbrain.
(13) In the latter tumors, a peculiar ataxic hemiparesis syndrome is produced by midbrain compression.
(14) Fewer, but still ample numbers, of SP-reactive axons are present also in the ventral tegmental and retrorubral areas of the midbrain tegmentum and in the ventral pallidum of the basal forebrain, but only sparse ME-reactive axons are present in these areas.
(15) In the investigation, the neocortex was represented by the frontal cortex (field 10), the old cortex by the hippocamp, the midbrain by black substance, and medulla oblongata by the inferior olive.
(16) The anxiolytic activity of serotonin agonists (buspirone, ipsapirone, campirone, caplapirone, 1-pyrimidinyl-piperazine) determined in rats on 3 experimental models of anxiety closely correlates with the degree of inhibition of impulse release of 3H-serotonin by electrically stimulated slices of the midbrain raphe dorsal nucleus (r = +0.85) but not the slices of the cerebral hemispheric cortex (r = +0.60) of the rats.
(17) The level of 5-HT was diminished in dorsal spinal cord and midbrain, whereas NE appeared unchanged.
(18) Movement-correlated firing was studied in 111 midbrain neurons recorded in freely behaving hamsters.
(19) These results suggest that different fibers with overlapping spatial distributions contribute to analgesia and vocalizations produced by midbrain stimulation.
(20) alpha-Fluoromethylhistidine, a histidine decarboxylase inhibitor, induced a significant depletion in the hypothalamic, midbrain, and cortical brain histamine amounts in 12- and 3-month-old rats.
Rostral
Definition:
(a.) Of or pertaining to the beak or snout of an animal, or the beak of a ship; resembling a rostrum, esp., the rostra at Rome, or their decorations.
Example Sentences:
(1) In the caudal spinal trigeminal nucleus (Vc), the collaterals of one half of the periodontium afferent fibers terminated mainly in lamina V at the rostral and middle levels of Vc.
(2) In addition, lightly immunostained cells were distinguished in the caudal portion of the hypothalamic arcuate nucleus, area of tuber cinereum, retrochiasmatic area, and rostral portion of the paraventricular thalamic nucleus after colchicine treatment.
(3) Other fusiform cells of the cPVN are oriented in a rostral-caudal plane and are situated more medially in this subdivision.
(4) Nonetheless, anatomical continuity was restored at the site of injury, axons projected across this region, and rostral spinal and brainstem neurons could be retrogradely labelled following HRP injections administered caudal to the lesion.
(5) We report the case of a premature infant, small for gestational age, who experienced rostral herniation of a portion of frontal lobe through the anterior fontanel as the result of a hemorrhagic cerebellar infarction followed by a large parieto-occipital intracerebral hemorrhage.
(6) Thus, Hox-1.6 is involved in regional specification along the rostrocaudal axis, but only in its most rostral domain of expression.
(7) Injection of the tracer substance wheat germ agglutinin-horseradish peroxidase (WGA-HRP) directly into the basilar pontine nuclei using a ventral surgical approach resulted in the labeling of somata in many areas both rostral and caudal to the basilar pons.
(8) Injection of horseradish peroxidase into the rostral ventrolateral medulla (RVLM) led to heavy retrograde and anterograde labeling in the region of the hypothalamus that yielded the CRDR when stimulated electrically.
(9) Electrical stimulation of the contralateral superior colliculus evoked monosynaptic field potentials which were largest in the caudal pontine reticular formation rostral to the abducens nucleus and in the rostral part of the medullary reticular formation caudal to the abducens nucleus.
(10) Labeled fibers and terminal-like structures were found 8-13 segments rostral and 1-5 segments caudal to the injected DRGs.
(11) A medium amount of degenerated terminals were observed in the nucleus pretectalis anterior (pars reticularis), the dorsal part of the periaqueductal grey at its most rostral levels, the caudolateral parts of the nucleus pretectalis posterior and the nucleus of optic tract, the H field of Forel, parts of the somatic cell columns of the oculomotor nucleus and the trochlear nucleus.
(12) The results indicate that NTS neurons containing a GRP-like peptide connect the rostral and caudal regions of the dorsal vagal complex by way of longitudinal nerve tracts descending NTS and TS.
(13) The type I neurons (27 X 43 mum) with four to seven primary dendrites were located mainly in the rostral and ventral areas of the LH.
(14) The rostral part shows only a few HRP-containing cells.
(15) The amine-induced contraction predominantly seen in the rostral arteries appears to be associated with activation of the alpha 1 adrenoceptor subtype.
(16) Respiratory modulation disappeared rostral to a section performed at the ponto-mesencephalic junction.
(17) P3.1 and P3.8 were identified only as farfield potentials in intracranial recordings from the pons and more rostral regions.
(18) The elopiform teleost Engraulis japonica was used for a light and electron microscopical study of the follicle epithelium in the rostral pars distalis of the pituitary.
(19) These responses were prominent in the rostral midbrain.
(20) To examine the effects of focally cooling three areas (rostral, intermediate, and caudal) of the ventral medullary surface (VMS) on respiratory oscillations in cervical sympathetic and phrenic nerve activity, 12 cats were anesthetized, vagotomized, paralyzed, and artificially ventilated with 7% CO2 in O2.