Development of the myotomal neuromuscular system in embryonic and larval angelfish, Pterophyllum scalare

Hirotaka Sakamoto, Masayuki Yoshida, Tatsuya Sakamoto, Kazumasa Uematsu

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

To reveal the developmental sequence of the myotomal neuromuscular system in a teleost angelfish, Pterophyllum scalare, we investigated the differentiation and axonal outgrowth of the somatic spinal motoneurons as well as the differentiation of the axial muscles by means of anatomical and histochemical methods. Acetylcholinesterase histochemistry and retrograde labeling with HRP revealed two large motoneurons in each spinal hemisegment in the late embryos. To clarify the posthatching change of the motoneuron number, the number of axons in the anal-level ventral root was counted, since ChAT-immunohistochemical labeling of cholinergic spinal neurons and electron microscopic observation in the adult showed that the ventral roots around the anal level contained only somatic motor axons. We found that 15 primary motoneurons in each spinal hemisegment participated in the muscle innervation in just-hatched larvae. The motor axons rapidly increased in number beyond the adult level within three days posthatching, and then decreased to reach the adult level within a few weeks. The result suggests that competition among the motoneurons for their target muscles takes place. To reveal the temporal sequence of differentiation of the myotomal muscle fibers, in addition to electron microscopic observation of the muscle, a fluorescent mitochondrial marker dimethylaminostyrylethylpyridiniumiodine (DASPEI) was used to detect red muscle fibers. In the late embryo, immature white muscle fibers subserving the twitching movement of the animal in the egg capsule were observed. Differentiation of the red muscle was not evident until day 10. The present results show that a complete set of the axial muscle motoneurons differentiates before the differentiation of the multiple muscle fiber types in the angelfish.

Original languageEnglish
Pages (from-to)775-784
Number of pages10
JournalZoological Science
Volume16
Issue number5
Publication statusPublished - Oct 1999
Externally publishedYes

Fingerprint

Pomacanthidae
motor neurons
muscle fibers
muscles
axons
embryo (animal)
electrons
cholinergic agents
histochemistry
innervation
acetylcholinesterase
Pterophyllum
neurons
immatures
larvae

ASJC Scopus subject areas

  • Animal Science and Zoology

Cite this

Development of the myotomal neuromuscular system in embryonic and larval angelfish, Pterophyllum scalare. / Sakamoto, Hirotaka; Yoshida, Masayuki; Sakamoto, Tatsuya; Uematsu, Kazumasa.

In: Zoological Science, Vol. 16, No. 5, 10.1999, p. 775-784.

Research output: Contribution to journalArticle

@article{578818e81ffe486fb8165c86f36ed6b5,
title = "Development of the myotomal neuromuscular system in embryonic and larval angelfish, Pterophyllum scalare",
abstract = "To reveal the developmental sequence of the myotomal neuromuscular system in a teleost angelfish, Pterophyllum scalare, we investigated the differentiation and axonal outgrowth of the somatic spinal motoneurons as well as the differentiation of the axial muscles by means of anatomical and histochemical methods. Acetylcholinesterase histochemistry and retrograde labeling with HRP revealed two large motoneurons in each spinal hemisegment in the late embryos. To clarify the posthatching change of the motoneuron number, the number of axons in the anal-level ventral root was counted, since ChAT-immunohistochemical labeling of cholinergic spinal neurons and electron microscopic observation in the adult showed that the ventral roots around the anal level contained only somatic motor axons. We found that 15 primary motoneurons in each spinal hemisegment participated in the muscle innervation in just-hatched larvae. The motor axons rapidly increased in number beyond the adult level within three days posthatching, and then decreased to reach the adult level within a few weeks. The result suggests that competition among the motoneurons for their target muscles takes place. To reveal the temporal sequence of differentiation of the myotomal muscle fibers, in addition to electron microscopic observation of the muscle, a fluorescent mitochondrial marker dimethylaminostyrylethylpyridiniumiodine (DASPEI) was used to detect red muscle fibers. In the late embryo, immature white muscle fibers subserving the twitching movement of the animal in the egg capsule were observed. Differentiation of the red muscle was not evident until day 10. The present results show that a complete set of the axial muscle motoneurons differentiates before the differentiation of the multiple muscle fiber types in the angelfish.",
author = "Hirotaka Sakamoto and Masayuki Yoshida and Tatsuya Sakamoto and Kazumasa Uematsu",
year = "1999",
month = "10",
language = "English",
volume = "16",
pages = "775--784",
journal = "Zoological Science",
issn = "0289-0003",
publisher = "Zoological Society of Japan",
number = "5",

}

TY - JOUR

T1 - Development of the myotomal neuromuscular system in embryonic and larval angelfish, Pterophyllum scalare

AU - Sakamoto, Hirotaka

AU - Yoshida, Masayuki

AU - Sakamoto, Tatsuya

AU - Uematsu, Kazumasa

PY - 1999/10

Y1 - 1999/10

N2 - To reveal the developmental sequence of the myotomal neuromuscular system in a teleost angelfish, Pterophyllum scalare, we investigated the differentiation and axonal outgrowth of the somatic spinal motoneurons as well as the differentiation of the axial muscles by means of anatomical and histochemical methods. Acetylcholinesterase histochemistry and retrograde labeling with HRP revealed two large motoneurons in each spinal hemisegment in the late embryos. To clarify the posthatching change of the motoneuron number, the number of axons in the anal-level ventral root was counted, since ChAT-immunohistochemical labeling of cholinergic spinal neurons and electron microscopic observation in the adult showed that the ventral roots around the anal level contained only somatic motor axons. We found that 15 primary motoneurons in each spinal hemisegment participated in the muscle innervation in just-hatched larvae. The motor axons rapidly increased in number beyond the adult level within three days posthatching, and then decreased to reach the adult level within a few weeks. The result suggests that competition among the motoneurons for their target muscles takes place. To reveal the temporal sequence of differentiation of the myotomal muscle fibers, in addition to electron microscopic observation of the muscle, a fluorescent mitochondrial marker dimethylaminostyrylethylpyridiniumiodine (DASPEI) was used to detect red muscle fibers. In the late embryo, immature white muscle fibers subserving the twitching movement of the animal in the egg capsule were observed. Differentiation of the red muscle was not evident until day 10. The present results show that a complete set of the axial muscle motoneurons differentiates before the differentiation of the multiple muscle fiber types in the angelfish.

AB - To reveal the developmental sequence of the myotomal neuromuscular system in a teleost angelfish, Pterophyllum scalare, we investigated the differentiation and axonal outgrowth of the somatic spinal motoneurons as well as the differentiation of the axial muscles by means of anatomical and histochemical methods. Acetylcholinesterase histochemistry and retrograde labeling with HRP revealed two large motoneurons in each spinal hemisegment in the late embryos. To clarify the posthatching change of the motoneuron number, the number of axons in the anal-level ventral root was counted, since ChAT-immunohistochemical labeling of cholinergic spinal neurons and electron microscopic observation in the adult showed that the ventral roots around the anal level contained only somatic motor axons. We found that 15 primary motoneurons in each spinal hemisegment participated in the muscle innervation in just-hatched larvae. The motor axons rapidly increased in number beyond the adult level within three days posthatching, and then decreased to reach the adult level within a few weeks. The result suggests that competition among the motoneurons for their target muscles takes place. To reveal the temporal sequence of differentiation of the myotomal muscle fibers, in addition to electron microscopic observation of the muscle, a fluorescent mitochondrial marker dimethylaminostyrylethylpyridiniumiodine (DASPEI) was used to detect red muscle fibers. In the late embryo, immature white muscle fibers subserving the twitching movement of the animal in the egg capsule were observed. Differentiation of the red muscle was not evident until day 10. The present results show that a complete set of the axial muscle motoneurons differentiates before the differentiation of the multiple muscle fiber types in the angelfish.

UR - http://www.scopus.com/inward/record.url?scp=0033248999&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033248999&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0033248999

VL - 16

SP - 775

EP - 784

JO - Zoological Science

JF - Zoological Science

SN - 0289-0003

IS - 5

ER -