Date of Award


Document Type



Edith Cowan University

Degree Name

Bachelor of Science Honours


Faculty of Communications, Health and Science

First Supervisor

Dr Peter Roberts

Second Supervisor

Dr Peter Burton


Leptin is a 16kDa peptide hormone that has recently been implicated in human reproductive processes. Like other hormones, leptin exerts its influence through its receptor. Of the three major isoforms of the receptor (OB-Ra, OB-Rb, and 0B-Re), OB-Ra (the dominant short form) has been implicated in transport processes within rat and human placentas, suggesting a role for it in implantation and pregnancy maintenance. The peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors that are a subfamily of nuclear hormone receptors. PPARs form heterodimers with another nuclear hormone receptor, RXRα, before binding to PPAR response elements (PPREs). Recently PPARϒ/RXRα heterodimers have been implicated in trophoblast differentiation, thus playing a key role in human implantation and placentation. The present study used Western Blot analysis to quantify the presence of Ob-R and PPARϒ protein in human placental tissue from first and second trimesters, and at term (n=9, n=10, n=12 respectively). PPARϒ and OB-Ra were found at all stages of pregnancy. Levels of OB-Ra were significantly lower in second trimester than in first trimester or at term (p