Submission Number: GER-4-16-9

Abstract Number: 498

DEVELOPMENTAL EXPRESSION OF THE FOLLICLE-STIMULATING HORMONE RECEPTOR mRNA IN THE BABOON FETAL OVARY.

Nicholas C Zachos* ¹, Reinhart B Billiar* ¹, Eugene D Albrecht* ² and Gerald J Pepe* ¹

Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA ¹
Departments of Obstetrics/Gynecology/Reproductive Sciences and Physiology, The Center for Studies in Reproduction, University of Maryland School of Medicine, Baltimore, MD ²

Abstract:
The development of ova and proliferation of follicles in the ovary occurs throughout fetal life and forms the foundation for normal reproductive function in adult life. In the adult, follicle-stimulating hormone (FSH) binds to its receptor (FSH-R) in granulosa cells to stimulate proliferation as well steroidogenesis, events critical to follicle development and reproductive capacity. Although serum FSH levels are elevated in the fetus during human and non-human primate pregnancy, our understanding of the role of FSH and the FSH-R in the regulation of the primate fetal ovary is incomplete. Therefore, the current study determined whether FSH-R mRNA is expressed in the baboon fetal ovary and if expression is correlated with follicular development. Ovaries were obtained from baboon fetuses delivered by cesarean section on days 60 (n=1), 100 (n=3), 140 (n=1), 165 (n=3) and 180 (n=2) of gestation (term = day184). Tissues were fixed in formalin for subsequent histology or frozen in liquid nitrogen and total RNA isolated by guanidinium isothiocyanate-cesium chloride centrifugation. FSH-R mRNA expression was determined by reverse-transcription-polymerase chain reaction (RT-PCR) using specific oligonucleotide primers within exons one and five of the human FSH-R, and which detected the human FSH-R cDNA as a single 342 bp product. The baboon fetal ovary was comprised almost exclusively of oogonia on days 60-100 of gestation, while folliculogenesis although initiated by day 100 was minimal. However, by day 140-165 of gestation the fetal ovary was comprised of an extensive number of primordial and/or primary follicles. In the fetal ovary, FSH-R mRNA was not expressed on day 60 and only minimally expressed on day 100 of gestation. However, FSH-R mRNA expression was extensive in fetal ovaries obtained on days 140, 165 and 180 of gestation and appeared to exceed that observed in the adult ovary during the menstrual cycle. In contrast, FSH-R mRNA was not detected in the adrenal, endometrium, or kidneys of adult baboons. These findings indicate that the baboon fetal ovary expresses FSH-R mRNA in a developmental pattern that appears to correlate with the ontogenesis and maturation of follicular development in utero. Supported by NIH NICHD HD 36207 Specialized Cooperative Centers Program in Reproduction Research.

Keywords: FSH receptor, fetal ovary, baboon

This abstract is being presented at: 8:00 AM in session:
Hormone Receptors