Expression of Platelet-Derived Growth Factor (PDGF) and PDGF α- and β-Receptors in the Peripheral Nervous System: An Analysis of Sciatic Nerve and Dorsal Root Ganglia

摘要

PreviousstudieshaveshownthatculturedSchwanncellssecreteplatelet-derivedgrowthfactor(PDGF)andexpressPDGFreceptorswhichtransmitamitogenicresponseparticularlywhentheirlevelsareupregulatedbyelevationofintracellularcAMP.InthisstudytheexpressionofPDGFandPDGF?±-and?2-receptorsintheperipheralnervoussystem(PNS)hasbeenexaminedbystudyingdorsalrootgangliaandsciaticnerve.Usingthemonoclonalanti-PDGFantibody,PGF-007,relativelyhighlevelsofPDGFweredetectedincellsoftheneonatalratdorsalrootgangliaandsciaticnerve.ThelocationandmorphologyofthesecellsindicatedthattheywereSchwanncellswhileneuronsofthedorsalrootgangliawerelessstronglylabeled.ThelevelsinSchwanncellsdeclinedduringthefirstpostnatalweeks.Intheadultrat,lowlevelsofPDGFweredetectedonmyelinatednervefiberswhileunmyelinatedfiberscontinuedtoexpresshigherlevelsofPDGF.AntiseraspecificforthePDGF?±-and?2-receptorrevealedhighlevelsofbothreceptorsintheneonatalratPNS.Intheadultratperipheralnervebothreceptorsweredetectableinunmyelinatednervefibers.ThePDGF?2-receptor,butnotthe?±-receptor,wasdetectedatlowlevelsonmyelinatednervefibers.Teasednervepreparations,aswellasfreshlydissociatedsciaticnervecells,wereusedtosubstantiatethefindingsinfrozentissuesections.NeuronsofthedorsalrootganglionexpressedPDGFandPDGF?±-and?2-receptorsinallthestagesofpostnataldevelopmentexamined.TheseresultsindicatethatPDGFmightplayaroleinthedevelopmentofthePNSandinmaintenanceofperipheralneurons.