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Published on: May 29, 2013
Neuroendocrine embryology and the APUD concept
Clinical Endocrinology
|January 1, 1976
Summary
Most peptide-producing cells in vertebrates are part of the amine precursor uptake and decarboxylation (APUD) cell series, likely originating from neuroectoderm. This suggests peptide endocrinology is a form of neuroendocrinology.
Area of Science:
- Neuroendocrinology
- Cell Biology
- Developmental Biology
Background:
- The amine precursor uptake and decarboxylation (APUD) cell series comprises the majority of hormonal peptide-producing cells in vertebrates.
- APUD cells are traditionally considered derivatives of neuroectoderm or specialized ectoderm.
- The precise origin of APUD cells in the gastrointestinal tract and pancreas remains debated, with some contrary evidence.
Purpose of the Study:
- To investigate the embryological origins of APUD cells.
- To determine the relationship between APUD cells and the nervous system.
- To re-evaluate the scope of peptide endocrinology.
Main Methods:
- Embryological studies in vertebrates.
- Immunocytochemical analysis of peptide distribution.
Main Results:
- The hypothalamohypophyseal complex is confirmed as neuroectodermal.
- Neural crest dispersion timing supports its contribution to foregut APUD cells.
- Placodal ectoderm contributes to pharyngeal pouch endocrine derivatives.
- Amphibian parathyroid glands share a neural ectodermal origin with the hypothalamo-hypophyseal axis.
- APUD series peptides are more widespread than previously known.
Conclusions:
- All peptide endocrinology can be classified as neuroendocrinology.
- APUD cells, along with some previously unclassified cells, constitute a third division of the nervous system: the Endocrine division.
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