Developmental pattern of three vesicular glutamate transporters in the myenteric plexus of the human fetal small intestine

Histol Histopathol. 2008 Aug;23(8):979-86. doi: 10.14670/HH-23.979.

Abstract

Three vesicular glutamate transporters (VGLUT1-3) have previously been identified in the central nervous system, where they define the glutamatergic phenotype, and their expression is tightly regulated during brain development. In the present study we applied immunocytochemistry to examine the distribution of the immunoreactivity of all three VGLUTs during prenatal development of the myenteric plexus in the human small intestine. We also investigated changes in their localization in the different segments of the small intestine and in the different compartments of the developing myenteric ganglia. Immunoreactivity against all three VGLUTs was found predominantly in the ganglionic neuropil, interganglionic varicose fibers and perisomatic puncta, but cytoplasmic labeling with different intensities also occurred. Each transporter displayed a characteristic spatiotemporal expression pattern, with the transient increase or decrease of immunoreactive cell bodies, varicosities or perisomatic puncta, depending on the fetal age, the gut segment or the ganglionic compartment. Throughout gestational weeks 14-23, VGLUT1 immunoreactivity always predominated over VGLUT2 immunoreactivity, though both peaked around week 20. VGLUT3 immunoreactivity was less abundant in the developing myenteric plexus than those of VGLUT1 and VGLUT2 immunoreactivity. It was mainly expressed in the ganglionic neuropil and in the perisomatic puncta throughout the examined gestational period. Neuronal perikarya immunoreactive for VGLUT3 were restricted to between weeks 18 and 20 of gestation and exclusively to the oral part of the small intestine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / metabolism
  • Fetal Development / physiology*
  • Fetus / metabolism*
  • Fluorescent Antibody Technique, Indirect
  • Gestational Age
  • Humans
  • Immunoenzyme Techniques
  • Intestine, Small / embryology*
  • Intestine, Small / metabolism
  • Myenteric Plexus / embryology*
  • Protein Isoforms
  • Vesicular Glutamate Transport Protein 1 / metabolism
  • Vesicular Glutamate Transport Protein 2 / metabolism
  • Vesicular Glutamate Transport Proteins / metabolism*

Substances

  • Biomarkers
  • Protein Isoforms
  • SLC17A6 protein, human
  • SLC17A7 protein, human
  • SLC17A8 protein, human
  • Vesicular Glutamate Transport Protein 1
  • Vesicular Glutamate Transport Protein 2
  • Vesicular Glutamate Transport Proteins