The Spinal Nerves of the Dogfish (Scyliorhinus)

1969 ◽  
Vol 49 (1) ◽  
pp. 51-75 ◽  
Author(s):  
B. L. Roberts
Keyword(s):  
Body Wall ◽  
Subcutaneous Tissue ◽  
Muscle Spindles ◽  
Motor Innervation ◽  
Spinal Nerves ◽  
Nerve Bundles ◽  
Spinal Roots ◽  
Tendon Organs ◽  
Physiological Isolation ◽  
Sensory Endings

The locomotory musculature of dogfish is innervated by the segmental spinal nerves. The sensory and motor innervation of the abdominal musculature was studied in a preparation consisting of a strip of the abdominal body wall innervated by the ventral rami of the spinal nerves.Each ventral ramus consists of two separate nerve bundles which were found to be peripheral extensions of the dorsal and ventral spinal roots. Recordings from the sensory bundles showed that there are few sensory endings in the musculature and body wall of the dogfish. It was possible to differentiate between ephemeral responses produced by cutaneous free-nerve endings and prolonged discharges which were generated by more specialized sensory endings. In some details these endings were found to be unlike either muscle spindles or tendon organs. Further, skinning experiments suggested that these mechanoreceptors lay in the skin or the very outer layers of the myotome.Histological searching, together with physiological isolation of units, suggested that these receptors were the corpuscular endings distributed sparsely amongst subcutaneous tissue. These endings are apparently the same as those described by Wunderer (1908) in the fins of elasmobranchs.

scholarly journals A Rare Case of Anterior Chest Wall Schwannoma Masquerading as a Breast Tumor

2014 ◽  
Vol 99 (3) ◽  
pp. 196-199 ◽  
Author(s):  
Takaaki Fujii ◽  
Reina Yajima ◽  
Hiroki Morita ◽  
Soichi Tsutsumi ◽  
Takayuki Asao ◽  
...  
Keyword(s):  
Peripheral Nerves ◽  
Breast Tumor ◽  
Breast Tissue ◽  
Subcutaneous Tissue ◽  
Anterior Chest Wall ◽  
The Body ◽  
Unusual Site ◽  
Current Case ◽  
Breast Parenchyma ◽  
Spinal Roots

Abstract A schwannoma is a tumor that develops on peripheral nerves or spinal roots. Although any part of the body can be affected, the breast is a quite unusual site for schwannomas. We report herein a case of schwannoma presenting as a breast tumor. In the current case, the tumor showed both clinically and mammographically as a well-defined breast mass. Of interest, sonographically, the well-defined mass appeared to be located in subcutaneous tissue, not in breast parenchyma, and this finding was confirmed histopathologically. These findings indicate the possibility that a schwannoma arising from subcutaneous breast tissue can show exophytic growth to the breast and appear as a breast tumor. In other words, our case implies the possible presence of a “pseudo” breast schwannoma.

scholarly journals The evolutionary origins and diversity of the neuromuscular system of paired appendages in batoids

2019 ◽  
Vol 286 (1914) ◽  
pp. 20191571 ◽  
Author(s):  
Natalie Turner ◽  
Deimante Mikalauskaite ◽  
Krista Barone ◽  
Kathleen Flaherty ◽  
Gayani Senevirathne ◽  
...  
Keyword(s):  
Body Wall ◽  
Spinal Nerves ◽  
Evolutionary Origins ◽  
Neuromuscular Systems ◽  
Terrestrial Habitats ◽  
Fundamental Pattern ◽  
Genetic Programme ◽  
Migratory Muscle Precursors ◽  
Fin Development ◽  
Appendage Patterning

Appendage patterning and evolution have been active areas of inquiry for the past two centuries. While most work has centred on the skeleton, particularly that of amniotes, the evolutionary origins and molecular underpinnings of the neuromuscular diversity of fish appendages have remained enigmatic. The fundamental pattern of segmentation in amniotes, for example, is that all muscle precursors and spinal nerves enter either the paired appendages or body wall at the same spinal level. The condition in finned vertebrates is not understood. To address this gap in knowledge, we investigated the development of muscles and nerves in unpaired and paired fins of skates and compared them to those of chain catsharks. During skate and shark embryogenesis, cell populations of muscle precursors and associated spinal nerves at the same axial level contribute to both appendages and body wall, perhaps representing an ancestral condition of gnathostome appendicular neuromuscular systems. Remarkably in skates, this neuromuscular bifurcation as well as colinear Hox expression extend posteriorly to pattern a broad paired fin domain. In addition, we identified migratory muscle precursors (MMPs), which are known to develop into paired appendage muscles with Pax3 and Lbx1 gene expression, in the dorsal fins of skates. Our results suggest that muscles of paired fins have evolved via redeployment of the genetic programme of MMPs that were already involved in dorsal fin development. Appendicular neuromuscular systems most likely have emerged as side branches of body wall neuromusculature and have been modified to adapt to distinct aquatic and terrestrial habitats.

Acupuncture Points of the Typical Spinal Nerves

1985 ◽  
Vol 13 (01n04) ◽  
pp. 39-47 ◽  
Author(s):  
H.C. Dung
Keyword(s):  
Body Wall ◽  
Acupuncture Point ◽  
The Body ◽  
Acupuncture Points ◽  
Spinal Nerves ◽  
Thoracic And Abdominal

Typical spinal nerves have six cutaneous branches which reach to the skin of the body wall in the thorax and abdomen. Each of these six cutaneous branches correlates to an acupuncture point. This communication describes acupuncture points found in the thoracic and abdominal walls using anatomic nomenclature relating to cutaneous branches of the spinal nerves.

On the structure of corpuscular proprioceptive endings in sharks

1976 ◽  
Vol 56 (4) ◽  
pp. 925-928 ◽  
Author(s):  
Q. Bone ◽  
A. D. Chubb
Keyword(s):  
Connective Tissue ◽  
Muscle Spindles ◽  
Second Order ◽  
The Body ◽  
Sensory Endings

Proprioceptive endings associated with the locomotor musculature are apparently extremely uncommon in fishes. Muscle spindles are absent, and only in elasmobranchs have sensory endings of two types been recognized as proprioceptive. One of these, found in sharks, is the coiled corpuscular ending first observed by Wunderer (1908) at the bases of the fins in various species. This type of ending also occurs sub-cutaneously along the body, superficial to the myocommata (Bone, 1964). Lowenstein (1956) examined the responses of the endings associated with the fin bases, and showed that they were slowly adapting mechanoreceptors, functioning as second order proprioceptors since as the fin was bent, so the connective tissue amongst which the endings lie was stretched or compressed, and the receptor discharged.

Motor innervation of the toad iris (Bufo marinus)

1976 ◽  
Vol 231 (4) ◽  
pp. 1272-1278 ◽  
Author(s):  
JL Morris
Keyword(s):  
Cranial Nerves ◽  
Bright Light ◽  
Light Response ◽  
Bufo Marinus ◽  
Motor Innervation ◽  
Pupillary Diameter ◽  
Direct Response ◽  
Transmural Stimulation ◽  
Spinal Roots ◽  
Stimulation Of

The sphincter pupillae muscle cells in the iris of Bufo marinus contract autonomously in response to bright light, causing a rapid constriction of the pupil. A strong sympathetic beta-adrenergic inhibition of the sphincter pupillae is apparent in this species. The inhibitory fibers can originate in the second, third, or fourth ventral spinal roots. No strong, consistent excitatory innervation of the toad iris was detected, even by transmural stimulation of the isolated iris. Pupilloconstriction occasionally resulted from stimulation of the 3rd or 5th cranial nerves, but the effect was small (10-20% of the magnitude of the light response) and inconsistent. It therefore appears that the toad must regulate pupillary diameter by balancing myogenic contraction, in direct response to light, against neurogenic (sympathetic) relaxation of the sphincter pupillae.

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