title: Atrial natriuretic factor receptor subtypes in the rat central nervous system.
abstract: In this study we investigated the presence and anatomical location of atrial natriuretic factor (ANF) receptor subtypes in the rat central nervous system using in vitro autoradiographic and cross-linking techniques. 125I-ANF-(Ser99-Tyr126) served as a labeled ligand, whereas ANF-(Ser99-Tyr126) and two peptides endowed with selectivity for ANF-C receptor--namely, C-ANF (des-[Gln116-Gly120] ANF-[Asp102-Cys121]-NH2) and ANF-(Phe106-Ile113)-NH2--were used as displacing agents. Distribution studies revealed the presence of specific ANF binding sites in a number of central nervous system areas examined. C-ANF at 10(-6) M competed for 125I-ANF binding to a much lower extent than ANF in many of those structures, whereas ANF-(106-113)-NH2 at 10(-6) M did not have a significant effect on the radioligand binding except in the choroid plexus, pia-arachnoid, and olfactory bulb. Analysis of the competition curves revealed that in the choroid plexus, pia-arachnoid, olfactory bulb, subfornical organ, area postrema, and habenular nucleus, ANF interacts with its binding sites with high affinity (IC50, 0.46-0.77 nM). In contrast, C-ANF and ANF-(106-113)-NH2 competed for 125I-ANF binding with high potency (IC50, 2-16 nM) in the choroid plexus and pia-arachnoid only, where they were able to displace 60-70% of the radioligand binding. 125I-ANF cross-linking to olfactory bulb membranes resolved a specific 120-kDa band corresponding to the high molecular weight receptor but did not disclose a specifically labeled band corresponding to the low molecular mass receptor.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Laboratory of Pathobiology, Clinical Research Institute of Montreal, Quebec, Canada.
authors.forename: E M
authors.initials: EM
authors.lastname: Konrad
authors.forename: G
authors.initials: G
authors.lastname: Thibault
authors.forename: E L
authors.initials: EL
authors.lastname: Schiffrin
authors.forename: M
authors.initials: M
authors.lastname: Cantin
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor; D001345:Autoradiography; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism*; D003432:Cross-Linking Reagents; D051381:Rats; D011919:Rats, Inbred Strains; D017461:Receptors, Atrial Natriuretic Factor; D011956:Receptors, Cell Surface / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D003432:Cross-Linking Reagents; D011956:Receptors, Cell Surface; C472610:atrial natriuretic peptide, rat; D009320:Atrial Natriuretic Factor; D017461:Receptors, Atrial Natriuretic Factor