Cuneate nucleus

About: Cuneate nucleus is a research topic. Over the lifetime, 614 publications have been published within this topic receiving 24859 citations. The topic is also known as: cuneate nucleus of spinal cord.

Afferent connections of the dorsal magnocellularis area of the cat red nucleus

Abstract: Location within the brain of retrogradely labeled neurons putting out projections from the dorsal magnocellularis area of the red nucleus was investigated by means of microiontophoretic injection of horseradish peroxidase into the dorsal magnocellularis area of the cat red nucleus. Projections were found from a number of hypothalamic nuclei, the centrum medianum, parafascicular and subthalamic nuclei, zone incerta, Forel's field, nucleus medialis habenulae, pontine and bulbar reticular formation, and the following midbrain structures: the central gray matter, superior colliculus, Cajal's interstitial nucleus, reticular formation, and the contralateral red nucleus. Projections were also identified proceeding from more caudally located structures: the cerebellar fastigial nucleus, facial nucleus, medial vestibular and dorsal lateral vestibular nuclei, and ventral horns of the spinal cord cervical segments. Connections between the substantia nigra and the red nucleus were clarified. Projections to the red nucleus from the cerebral cortex, interstitial and dentate (lateral) cerebellar nuclei, the nucleus gracilis and cuneate nucleus were found, confirming data presented in the literature. Bilateral trajectories of retrogradely labeled fiber systems are described.

Research report C projections of sensory innervation of the rat superficial temporal artery

Abstract: Elucidating the central sensory projection pathways of extra- and intracranial vessels appears to be of fundamental importance for understanding the pathogenetic mechanisms of primary headaches. In this paper, two kinds of tracers, choleragenoid (cholera toxin subunit b, CTb) and wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP), were used to transganglionically label the central sensory projections of the innervation of the superficial temporal artery (STA). Following either of the tracers applied on the adventitia of the STA, labelled terminations were found mainly in the ipsilateral C1–C3 spinal dorsal horns. Sparse labelling was also found in the interpolar and caudal parts of the spinal trigeminal nucleus. In the spinal cord, CTb labelled profiles were mainly located in laminae III and IV, whereas WGA-HRP labelled profiles were mainly located in laminae I and II. In the medulla, CTb but not WGA-HRP labelled terminals were found in a small dorsolateral extension of the cuneate nucleus. The present results indicate that the primary sensory nervous center of the STA is located in the rostral cervical spinal dorsal horn. The caudal parts of the spinal trigeminal nucleus, which has been demonstrated as a center of pain and temperature sensations of the head and face, transmits limited information from the STA to higher nervous centers.  2002 Elsevier Science B.V. All rights reserved. Theme: Sensory systems Topic: Somatic and visceral afferents

Simultaneous HPLC and Evoked Potential Analysis of Cat Cuneate Nucleus

Abstract: The transmission of somatosensory information through the cuneate nucleus is subserved by both electrical and chemical activity. The present work seeks to demonstrate the concurrent assessment of both types of activity in the anesthetized, immobilized cat. Further information on this work appears elsewhere.' FIGURE 1 shows representative data. The inner tip of the concentric push-pull cannula' is positioned at the exposed brainstem-pial surface. Neuronal activity is elicited by electrical stimulation of the left superficial radial nerve (LSRN, a direct cuneate projection). High performance liquid chromatography with electrochemical detection (HPLC-EC) analysis of perfusate recovered during control (A) and subsequent LSRN electrical stimulation (B) periods differ in the presence of a 26-minute elution peak. LSRN stimulation also evoked cuneate surface potentials (B:right); sequential waveform components' are due to: primary afferent axonal impulses (P,), cuneothalamic neurons depolarization (N,), primary afferent terminal depolarization (Pz), and delayed relayed activity via corticofugal projections (N2). Interpretation of neurochemical with concurrent electrophysiological data assumes that perfusion and electrical recording volumes overlap extensively and include primary and relayed synaptic loci. Then, the data reveal that expected electrical activity of cuneate neurons occurs during push-pull perfusion and detectable neurochemical content changes with cuneate electrical activity. These data do not reveal the time course of entry of detected neurochemical into the sample recovered during perfusion.