A major role of the corpus luteum (CL) is to produce progesterone (P4). The CL has immature vasculature shortly after ovulation, suggesting it exists under hypoxic conditions. Hypoxia-inducible factor-1 (HIF1) induces the expression of glucose transporter 1 (GLUT1). To clarify the physiological roles of GLUT1 in bovine CL, we examined GLUT1 mRNA expression in the CL under hypoxic conditions by ...

In the menstrual cycle, extensive angiogenesis accompanies luteinization. During luteolysis, endothelial cells die, whereas in a conceptual cycle, the corpus luteum (CL) persists, and endothelial cell survival is extended. A main stimulator for angiogenesis is vascular endothelial growth factor (VEGF), while the angiopoietins (Ang-1 and Ang-2) may be important modulators. The aim of this study ...

The present study was designed to construct reliable daily salivary progesterone profiles throughout the luteal phase to accurately evaluate the corpus luteum function. Furthermore, we investigated the clinical relevance of a simple midluteal salivary progesterone estimation for the diagnosis of luteal phase insufficiency by determining the diagnostic efficiency and cutoff values. A total of 12...

The matrix metalloproteinases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteinases (TIMPs), may mediate the dramatic structural and functional changes in the corpus luteum (CL) over the course of its life span. In addition to regulating MMP activity, TIMPs are also involved in a variety of cellular processes, including cell proliferation and steroidogenesis. In a seri...

Effects of procaine on dibutyryl adenosine 3',5'-cyclic monophosphate ((Bu)2cAMP)-, Ca2(+)- or forskolin-induced steroidogenesis were examined in isolated bovine adrenocortical cells. Procaine (less than 1.0 mM) caused a marked suppression of (Bu)2cAMP- or forskolin-induced steroidogenesis in the absence of extracellular Ca2+, but did not affect on Ca2(+)-induced steroidogenesis in the cells. (...

The midcycle luteinizing hormone (LH) surge triggers several tightly linked ovarian processes, including steroidogenesis, oocyte maturation, and ovulation. We designed studies to determine whether epidermal growth factor receptor (EGFR)-mediated signaling might serve as a common regulator of these activities. Our results showed that EGF promoted steroidogenesis in two different in vitro models ...

Intracellular cAMP and Ca(2+) are involved in the regulation of steroidogenic activity in Leydig cells, which coordinate responses to luteinizing hormone (LH) and human chorionic gonadotropin (hCG). However, the identification of Ca(2+) entry implicated in Leydig cell steroidogenesis is not well defined. The objective of this study was to identify the type of Ca(2+) channel that affects Leydig ...

BACKGROUND Blood flow in the corpus luteum (CL) is associated with luteal function. The present study was undertaken to investigate whether luteal function can be improved by increasing CL blood flow in women with luteal phase defect (LFD). METHODS Blood flow impedance in the CL was measured by transvaginal color-pulsed-Doppler-ultrasonography and was expressed as a resistance index (RI). The...