ISSN:
1573-6830
Keywords:
neuropeptide Y (NPY)
;
peptide YY (PYY)
;
NPY receptor
;
PYY receptor
;
quantitative receptor autoradiography
;
rat brain
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 1. Specific binding sites for neuropeptide Y (NPY) and peptide YY (PYY) were investigated in rat brain areas using quantitative receptor autoradiography with125I-Bolton-Hunter NPY (125I-BH-NPY) and125I-PYY, radioligands for PP-fold family peptides receptors. 2. There were no differences between localization of125I-BH-NPY and125I-PYY binding sites in the rat brain. High densities of the binding sites were present in the anterior olfactory nucleus, lateral septal nucleus, stratum radiatum of the hippocampus, posteromedial cortical amygdaloid nucleus, and area postrema. 3. In cold ligand-saturation experiments done in the presence of increasing concentrations of unlabeled NPY and PYY,125I-BH-NPY and125I-PYY binding to the stratum radiatum of the hippocampus, layer I of the somatosensory frontoparietal cortex, molecular layer of the cerebellum, and area postrema was single and of a high affinity. There was a significant difference between the affinities of125I-BH-NPY (K d = 0.96 nM) and125I-PYY binding (K d = 0.05 nM) to the molecular layer of the cerebellum. The binding of the two radioligands to the other areas examined had the same affinities. 4. When comparing the potency of unlabeled rat pancreatic polypeptide (rPP), a family peptide of NPY and PYY, to inhibit the binding to the areas examined, rPP displaced125I-BH-NPY and125I-PYY binding to the area postrema more potently than it did the binding to the stratum radiatum of the hippocampus, layer I of the somatosensory frontoparietal cortex, and molecular layer of the cerebellum. 5. Thus, the quantitative receptor autoradiographic method with125 I-BH-NPY and125I-PYY revealed differences in binding characteristics of specific NPY and PYY binding sites in different areas of the rat brain. The results provide further evidence for the existence of multiple NPY-PYY receptors in the central nervous system.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00712847
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