title: PDGF and its receptors in the developing rodent retina and optic nerve.
abstract: We have used in situ hybridization to visualize cells in the developing rat retina and optic nerve that express mRNAs encoding the A and B chains of platelet-derived growth factor (PDGF-A and PDGF-B), and the alpha and beta subunits of the PDGF receptor (PDGF-alpha R and PDGF-beta R). We have also visualized PDGF-A protein in these tissues by immunohistochemistry. In the retina, PDGF-A mRNA is present in pigment epithelial cells, ganglion neurons and a subset of amacrine neurons. PDGF-A transcripts accumulate in ganglion neurons during target innervation and in amacrine neurons around the time of eye opening, suggesting that PDGF-A expression in these cells may be regulated by target-derived signals or by electrical activity. In the mouse retina, PDGF-A immunoreactivity is present in the cell bodies, dendrites and proximal axons of ganglion neurons, and throughout the inner nuclear layer. PDGF-alpha R mRNA is expressed in the retina by astrocytes in the optic fibre layer and by a subset of cells in the inner nuclear layer that might be Müller glia or bipolar neurons. Taken together, our data suggest short-range paracrine interactions between PDGF-A and PDGF-alpha R, the ligand and its receptor being expressed in neighbouring layers of cells in the retina. In the optic nerve, PDGF-A immunoreactivity is present in astrocytes but apparently not in the retinal ganglion cell axons. PDGF-alpha R+ cells in the optic nerve first appear near the optic chiasm and subsequently spread to the retinal end of the nerve; these PDGF-alpha R+ cells are probably oligodendrocyte precursors (Pringle et al., 1992). RNA transcripts encoding PDGF-B and PDGF-beta R are expressed by cells of the hyaloid and mature vascular systems in the eye and optic nerve.
authors.affiliation: Department of Biology, University College London, UK.
authors.forename: H S
authors.initials: HS
authors.lastname: Mudhar
authors.forename: R A
authors.initials: RA
authors.lastname: Pollock
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: C D
authors.initials: CD
authors.lastname: Stiles
authors.forename: W D
authors.initials: WD
authors.lastname: Richardson
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000737:chemistry; D001369:Axons / Q000737:chemistry; D001792:Blood Platelets / Q000737:chemistry; D001808:Blood Vessels / Q000737:chemistry; D003712:Dendrites / Q000737:chemistry; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D009457:Neuroglia / Q000737:chemistry; D009474:Neurons / Q000737:chemistry; D009900:Optic Nerve / Q000737:chemistry / Q000196:embryology*; D010982:Platelet-Derived Growth Factor / Q000032:analysis*; D011505:Protein-Tyrosine Kinases / Q000032:analysis; D011518:Proto-Oncogene Proteins / Q000032:analysis; D020574:Proto-Oncogene Proteins c-sis; D051381:Rats; D017207:Rats, Sprague-Dawley; D017479:Receptors, Platelet-Derived Growth Factor / Q000032:analysis*; D012160:Retina / Q000737:chemistry / Q000196:embryology*
chemical_list: D010982:Platelet-Derived Growth Factor; D011518:Proto-Oncogene Proteins; D020574:Proto-Oncogene Proteins c-sis; C075278:platelet-derived growth factor A; D011505:Protein-Tyrosine Kinases; D017479:Receptors, Platelet-Derived Growth Factor