title: Temporal expression of platelet-derived growth factor (PDGF)-A and its receptor in human preimplantation embryos.
abstract: In order to improve assisted fertilization in humans it is important to elucidate the mechanisms of control of growth and development in the early pre-embryo. Increasing evidence shows that growth factors are of importance for such control mechanisms. As platelet-derived growth factor (PDGF) has been shown to enhance growth in a number of tissues, it may also be important in human pre-embryo development. PDGF acts as a dimer (AA, BB or AB) through its receptors: alpha alpha, beta beta and alpha beta. In order to study the role of PDGF and its receptors, we have used reverse transcription-polymerase chain reaction (RT-PCR) to examine the presence of transcripts in human pre-embryos that were surplus from the in-vitro fertilization treatment of infertile couples. Transcripts for PDGF A were present in the oocyte, 8-cell, morula and blastocyst stages but not in the 4-cell stage. Transcripts for PDGF B were not detected at any stage. PDGF receptor (PDGFR)-alpha transcripts were found in the 4-cell, 8-cell and blastocyst stages but not in the oocyte or morula stages. Transcripts for PDGFR-beta were detected from the 8-cell, morula and blastocyst stages but not in the oocyte or 4-cell stages. These results show that mRNA synthesis of both PDGF A and the two receptor subunits alpha and beta takes place from the 8-cell stage onwards, suggesting an autostimulatory pathway as a possible mechanism for growth factors during pre-embryo development.
authors.affiliation: Neonatal and Reproduction Laboratory, Karolinska Institute, Stockholm, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Osterlund
authors.forename: H
authors.initials: H
authors.lastname: Wramsby
authors.forename: A
authors.initials: A
authors.lastname: Pousette
mesh_terms: D001755:Blastocyst / Q000378:metabolism*; D017931:DNA Primers; D005260:Female; D006801:Humans; D009865:Oocytes / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis* / Q000235:genetics; D016133:Polymerase Chain Reaction; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics; D020574:Proto-Oncogene Proteins c-sis; D012333:RNA, Messenger / Q000032:analysis; D020796:Receptor, Platelet-Derived Growth Factor alpha; D020797:Receptor, Platelet-Derived Growth Factor beta; D017479:Receptors, Platelet-Derived Growth Factor / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D017931:DNA Primers; D010982:Platelet-Derived Growth Factor; D011518:Proto-Oncogene Proteins; D020574:Proto-Oncogene Proteins c-sis; D012333:RNA, Messenger; C075278:platelet-derived growth factor A; D020796:Receptor, Platelet-Derived Growth Factor alpha; D020797:Receptor, Platelet-Derived Growth Factor beta; D017479:Receptors, Platelet-Derived Growth Factor