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Updated: Jun 1, 2026
06:59
Characterization of Metabolic Status in Nonhuman Primates with the Intravenous Glucose Tolerance Test
Published on: November 13, 2016
The brainstem preproglucagon system in a non-human primate (Macaca mulatta)
1gubra ApS, Agern Allé 1, 2970 Hørsholm, Denmark. niels@gubra.dk
Brain Research
|May 27, 2011
Summary
This study maps glucagon-like peptide-2 (GLP-2) neurons in primate brains, revealing projections to the hypothalamus. These findings highlight conserved brainstem pathways and denser hypothalamic innervation in primates compared to rodents.
Area of Science:
- Neuroscience
- Endocrinology
- Primate Anatomy
Background:
- Preproglucagon neurons in the brainstem produce glucagon-like peptides (GLP-1, GLP-2) and oxyntomodulin.
- Rodent neuroanatomy of these neurons is known, but primate projections are uncharacterized.
Purpose of the Study:
- To map the location and projections of preproglucagon neurons in non-human primates.
- To compare primate GLP-2 neuronal systems with rodent models.
Main Methods:
- Radioactive in situ hybridization to detect preproglucagon mRNA.
- Immunohistochemistry using an antibody against GLP-2.
Main Results:
- Preproglucagon mRNA and GLP-2-immunoreactive cell bodies were found in the caudal nucleus of the solitary tract and adjacent areas.
- Prominent GLP-2-immunoreactive terminal fields were identified in the hypothalamus (PVN, DMH, Arc) and bed nucleus of the stria terminalis.
- Primate brains showed denser GLP-2 innervation in the mediobasal hypothalamus compared to rodents.
Conclusions:
- The brainstem preproglucagon neuronal system is conserved between rats and non-human primates.
- Primate GLP-2 neurons project extensively to hypothalamic regions, particularly the arcuate nucleus.
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