The projection of primary afferent fibers to the gracile nucleus was studied during development. Injections of wheat germ agglutinin-horseradish peroxidase were made into the hindlimb of fetal, postnatal and adult rats. In most cases the sections were alternately stained for wheat germ agglutinin-horseradish peroxidase including counter stain with Neutral red and for acetylcholinesterase. At embryonic day 17 labelled fibers could be traced to the mid-cervical spinal cord but not further rostrally. At embryonic days E18 and E19 labelled fibers penetrate the rostral pole of the nucleus, which does not happen more caudally. At embryonic day E21 the caudal-most pole of the gracile nucleus still is not penetrated by labelled fibers. From postnatal day 1 onwards labelled fibers are found throughout the entire rostrocaudal extent of the gracile nucleus. These results suggest that primary afferent fibers from the hindlimb first grow to the rostral pole of the gracile nucleus and penetrate the rostral pole immediately upon their arrival. During further development more caudal parts of the gracile nucleus are gradually penetrated in a rostrocaudal fashion by primary afferent fibers of the hindlimb.
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Adv Sci (Weinh)
January 2025
Shandong Key Laboratory of Mental Disorders and Intelligent Control, The Second Hospital of Shandong University, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, 250012, China.
J Integr Med
September 2024
Lundquist Institute for Biomedical Innovation, Harbor-University of California at Los Angeles (UCLA) Medical Center, Torrance, CA 90502, USA; Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA and Harbor-UCLA Medical Center, Torrance, CA 90502, USA. Electronic address:
Numerous studies from different international groups have demonstrated that sensations can be propagated along acupuncture channel pathways. The propagated sensation along the channel pathway (PSCP) can be elicited by electroacupuncture (EA), transcutaneous electrical nerve stimulation (TENS), manual acupuncture (MA), and heat applied to distal acupuncture points (acupoints). Nitric oxide (NO) levels were reported to be elevated in the gracile nucleus and skin regions near to the EA sites, with higher levels at acupoints associated with an enhanced expression of NO synthase and transient receptor potential vanilloid type 1.
View Article and Find Full Text PDFAnat Rec (Hoboken)
July 2024
Department of Anatomy, Jinzhou Medical University, Jinzhou, Liaoning, China.
Nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase (N-d) positive neurons have been extensively studied across various animals, and N-d neurodegenerative neurites have been detected in some aged animal models. However, detailed knowledge on N-d positivity and aging-related alterations in the spinal cord and medulla oblongata of pigeons is limited. In this study, we investigated N-d positivity and age-related changes in the pigeon's spinal cord and medulla oblongata and compared them to those in rats and mice.
View Article and Find Full Text PDFCereb Cortex
June 2024
Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, United States.
Nonpainful tactile sensory stimuli are processed in the cortex, subcortex, and brainstem. Recent functional magnetic resonance imaging studies have highlighted the value of whole-brain, systems-level investigation for examining sensory processing. However, whole-brain functional magnetic resonance imaging studies are uncommon, in part due to challenges with signal to noise when studying the brainstem.
View Article and Find Full Text PDFGenome Biol Evol
July 2024
Natural History Museum, University of Oslo, Blindern, P.O. Box 1172, 0318 Oslo, Norway.
Genome-wide information has so far been unavailable for ribbon worms of the clade Hoplonemertea, the most species-rich class within the phylum Nemertea. While species within Pilidiophora, the sister clade of Hoplonemertea, possess a pilidium larval stage and lack stylets on their proboscis, Hoplonemertea species have a planuliform larva and are armed with stylets employed for the injection of toxins into their prey. To further compare these developmental, physiological, and behavioral differences from a genomic perspective, the availability of a reference genome for a Hoplonemertea species is crucial.
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