Bioscientifica Proceedings

The GnRH receptor plays a pivotal role in reproduction. This review summarizes current knowledge of the regulation of GnRH receptor gene expression by endocrine factors in sheep and cattle. Expression of the GnRH receptor gene, measured by steady-state amounts of GnRH receptor messenger RNA (mRNA), is maximal during the preovulatory period. The molecular events leading to maximal GnRH receptor gene expression are probably triggered by decreased circulating concentrations of pr...

Summary. Limiting the abundance of free-ranging ungulate populations is a significant issue for natural resource managers in many areas of North America. Hunting and culling have traditionally been used to regulate wild animal numbers but there are a growing number of circumstances where these methods pose significant legal, ethical, and ecological challenges, and resource managers often seek alternative approaches to population control. Decreasing fertility o...

Experiments were conducted to further our understanding of the cellular and molecular mechanisms that regulate luteal function in ewes. Inhibition of protein kinase A (PKA) reduced (P < 0.05) secretion of progesterone from both small and large steroidogenic luteal cells. In addition, the relative phosphorylation state of steriodogenic acute regulatory protein (StAR) was more than twice as high (P&hairsp;<&hairsp;0.05) in large vs small luteal cells. Large steroidogenic...