(n.) The middle segment of the brain; the midbrain. Sometimes abbreviated to mesen. See Brain.
Example Sentences:
(1) 5-HT containing terminals and fibers also were observed in the mesencephalon and appeared to run rostrally in the medial part of the medial forebrain bundle.
(2) Effects of noxious electrical tooth stimulations and intraarterial administration of bradykinin or inhalation of volatile anesthetics on substance P content in the diencephalon-mesencephalon, pons-medulla and the spinal cord were examined in the rat.
(3) In order to study the interactions between serotonergic mechanism and electrical stimulation of the mesencephalic central gray substance, rats were trained to lever-press for terminating aversive electric stimuli applied at the Periaqueductal gray and adjoining tectum of the mesencephalon.
(4) The activity of glycerophosphorylcholine phosphodiesterases was determined in the mesencephalon, diencephalon, cerebral hemispheres, cerebellum and olfactory bulb during postnatal development from P5 to P70 of rat brain.
(5) In addition, these amines caused a concurrent change in the release of ACh at perfusion loci in both thalamus and mesencephalon.
(6) Levels of acetylcholine were significantly elevated in the telencephalon and diencephalon + mesencephalon of rats killed by near-freezing during conditioned suppression of food-reinforced lever pressing, whereas levels of serotonin, dopamine, and norepinephrine were not altered.
(7) The onset of convulsions induced by these convulsants coincides with the fall in GABA content and GAD activity in the mesencephalon area, and in contrast, the cessation of the convulsions by PN supplement coincides with the recovery in both the parameters.
(8) However, a later component of the Cnf-AEP whose generation locus within the mesencephalon is unknown was modulated by bf stimulation.
(9) Six hours after treatment with AOAA the GABA levels in the cerebellum, the cortex, the ventral mesencephalon and the striatum.
(10) Responses of substantia nigra zona compacta neurons to nomifensine and amantadine were studied with intracellular recording techniques (current and voltage clamp) in in vitro slice preparation of rat mesencephalon.
(11) These results describe a novel neurochemical system within the rat basal ganglia that is regulated by dopaminergic innervation from the mesencephalon.
(12) The left vertebral angiography revealed an anteriovenous malformation in the mesencephalon mainly feeded by the thalamoperforate artery and the medial branch of the posterior choroidal artery.
(13) (1) In 27 animals microinjection of 25--100 ng of angiotensin II through chronic cannulae implanted in the preoptic region initiated drinking and in subsequent acute experiments influenced the spontaneous discharge rate of single neurons in the ipsi-lateral mesencephalon.
(14) Into the second week of embryo growth (E7-E15), GABA appears in the mesencephalon (E7) and the eye (E9-E10).
(15) Behavioral augmentation also has been shown with opioids such as morphine, and it is known that a stimulant action on dopaminergic perikarya in the ventromedial mesencephalon is critical to the development of behavioral sensitization to morphine.
(16) Since EKC- and NANM-induced cardiovascular and respiratory depression were not observed in conscious intact or chronic spinal dog, it is suggested that: 1) kappaergic system rostral to mesencephalon may play a role in counteracting these depressant effects of EKC; 2) sigma receptor-mediated tachypnea and tachycardia are dissociable; the tachypneic effect may be mediated through higher center while the medulla oblongata is involved in producing tachycardia.
(17) Critical points of changing axial orientation were identified at the mesencephalon, the Rathke pouch and third branchial arch, and with the hepato-cardio-respiratory complex split between the 2 axes.
(18) The local cerebral blood flow and oxygen tension in the brain cortex, the reticular formation of the mesencephalon and the posterior hypothalamus were studied in chronic experiments in non-anesthetized rabbits with experimentally induced myocardial infarction.
(19) The variation was in the order leptomeninges greater than hypothalamus greater than cerebral cortex = mesencephalon greater than cerebellum = brain stem.
(20) In the present work, using the indirect peroxidase-labelled antibody technique, we made a comparative study about the distribution of Met-enkephalin-like-immunoreactive (ELI)-cell bodies in rat mesencephalon; comparing animals that received colchicine into the lateral ventricle and animals that got the colchicine injected into different cerebral nuclei.
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.