A Morphometric Examination of the Ultrastructure of Regenerating Hypoglossal Motoneurons from the Rat and Analysis of Thyroid Hormone Influence on Motoneuron Structure and Regeneration

Abstract

The ultrastructure of regenerating hypoglossal motoneurons and their response to altered thyroid hormone status were examined. Morphometric techniques were utilized to evaluate uninjured and axotomized hypoglossal motoneurons from the rat. Hypoglossal nucleus volume and neuronal size were estimated from 50 micron sections. The volume and surface area of cell body organelles were determined from one micron and ultrathin sections. Seven to 30 days following axotomy the volume of the hypoglossal nucleus was significantly diminished (p<0.05). Significant neuronal enlargement (p<0.05) was detected 13 and 21 days following axotomy. Subcellular alterations were most prominent 7 days following nerve transection: nucleolar volume was augmented, rough endoplasmic reticulum surface area was reduced, and non-Golgi smooth membrane surface area increased (p<0.05). Other organelles resisted the influence of axotomy. Ultrastructural parameters returned to control levels by 30 days following the nerve transection.

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Document Details

Document Type
Technical Report
Publication Date
Jul 14, 1988
Accession Number
ADA634930

Entities

People

  • Laura L. Hall

Organizations

  • Uniformed Services University of the Health Sciences

Tags

DTIC Thesaurus Topics

  • Arteries
  • Autonomic Nervous System
  • Blood
  • Brain
  • Cell Membrane
  • Cell Nucleus
  • Cell Nucleus Structures
  • Cells
  • Cellular Structures
  • Chemistry
  • Endoplasmic Reticulum
  • Health Services
  • Neurons
  • Organelles
  • Peripheral Nervous System
  • Thyroid Hormones

Fields of Study

  • Biology

Readers

  • Cardiovascular Physiology
  • Circadian Sleep-Wake Regulation and Chronobiology
  • Molecular and Cellular Biochemistry