This Article Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by CHEN, C.-F. Articles by TANIZAWA, O. Search for Related Content PubMed PubMed Citation Articles by CHEN, C.-F. Articles by TANIZAWA, O.

Changes in Epidermal Growth Factor Receptor and Its Messenger Ribonucleic Acid Levels in Human Placenta and Isolated Trophoblast Cells During Pregnancy

Department of Obstetrics and Gynecology, Osaka University Medical School Osaka 553, Japan

Address all correspondence and requests for reprints to: Dr. Hirohisa Kurachi, Department of Obstetrics and Gynecology, Osaka University Medical School, 1-1-50, Fukushima, Fukushima-ku, Osaka 553, Japan.

We measured the amounts of epidermal growth factor receptor (EGFR) in plasma membrane fractions purified from early, middle, and term placentas and from isolated trophoblast cells, and the amounts of EGFR mRNA were measured in whole placentas. Binding studies were performed using [¹²⁵I] human EGF as ligand; two classes (high and low) of binding sites were found in placental and trophoblast cell plasma membranes. Although dissociation constants (Kd) were not significantly different in placental plasma membranes from the three stages of pregnancy, the number of binding sites increased significantly during pregnancy. The mean numbers of binding sites were 0.72 ± 0.18 (±SE), 1.02 ± 0.10, and 1.89 ± 0.21 pmol/mg protein (high affinity sites) in plasma membrane fractions from early, middle, and term whole placentas, respectively. A similar significant increase was found when the membranes were prepared from isolated trophoblast cells. At the same time, total cellular RNA was isolated, denatured, and blotted onto nitrocellulose membranes. Then, hybridization with ³²P-labeled pE 7, a cDNA of EGFR, or ³²P-labeled v-erb-B oncogene, autoradiography, and densitometry were performed. The EGFR mRNA increased proportionally to the changes in EGFR during pregnancy. These results indicate that EGF-binding sites and EGFR production increase in human placentas throughout the gestational period.

Received March 29, 1988.

This article has been cited by other articles:

				Y. Okamoto, M. Sakata, K. Ogura, T. Yamamoto, M. Yamaguchi, K. Tasaka, H. Kurachi, M. Tsurudome, and Y. Murata Expression and regulation of 4F2hc and hLAT1 in human trophoblasts Am J Physiol Cell Physiol, January 1, 2002; 282(1): C196 - C204. [Abstract] [Full Text] [PDF]

				Y. Kamei, O. Tsutsumi, A. Yamakawa, Y. Oka, Y. Taketani, and J. Imaki Maternal Epidermal Growth Factor Deficiency Causes Fetal Hypoglycemia and Intrauterine Growth Retardation in Mice: Possible Involvement of Placental Glucose Transporter GLUT3 Expression Endocrinology, September 1, 1999; 140(9): 4236 - 4243. [Abstract] [Full Text]