Development of prostaglandin endoperoxide synthase expression in the ovine fetal central nervous system and pituitary.

In this study, we tested the hypothesis that prostaglandin endoperoxide synthase-1 and -2 (PGHS-1 and PGHS-2) are expressed throughout the latter half of gestation in ovine fetal brain and pituitary. Hypothalamus, pituitary, hippocampus, brainstem, cortex and cerebellum were collected from fetal sheep at 80, 100, 120, 130, 145days of gestational age (DGA), 1 and 7days postpartum lambs, and from adult ewes (n=4-5 per group). mRNA and protein were isolated from each region, and expression of prostaglandin synthase-1 (PGHS-1) and -2 (PGHS-2) were evaluated using real-time RT-PCR and western blot.

Development of ER-alpha and ER-beta expression in the developing ovine brain and pituitary.

Fetal neuroendocrine development in late gestation is critical for maintenance of fetal homeostasis, growth, and readiness for birth. We designed the present study to identify the regional patterns of expression of the two main isoforms of the estrogen receptor, ER-alpha and ER-beta, in the developing ovine fetal brain. Fetal (80, 100, 120, 130, and 145 days gestation), neonatal (1 and 7 days), and adult sheep were euthanized and the following tissues were collected: pituitary, hypothalamus, hippocampus, cerebral cortex, and brainstem.

Genomic analysis of neuroendocrine development of fetal brain-pituitary-adrenal axis in late gestation.

The present study was performed to identify the changes in genomic expression of critical components of the hypothalamus-pituitary-adrenal (HPA) axis in the second half of gestation in fetal sheep. We isolated mRNA from pituitary, hypothalamus, hippocampus, and brain stem in fetal sheep at 80, 100, 120, 130, and 145 days of gestation and 1 and 7 days after delivery (n = 4-5/group). Using real-time RT-PCR, we measured mRNA expression levels of glucocorticoid receptor (GR), mineralocorticoid receptor (MR), serum- and glucocorticoid-induced kinase-1 (sgk1), proopiomelanocortin (POMC), CRF, and arginine vasopressin (AVP).

Developmental expression of chemokine receptor genes in the human fetus.

Background: Chemokines induce cell motility during embryogenesis by activating specific receptors. While the orchestration of organogenesis is complex and requires the interaction of many morphoregulatory molecules that lead to coordinated organ development, limited knowledge exists regarding the human developmental biology of chemokines and their receptors. Such information on chemokine receptor expression could potentially enhance our understanding of organogenesis in the normal human fetus.

Effects of enterally administering granulocyte colony-stimulating factor to suckling mice.

Gastrointestinal (GI) tract development is influenced by multiple growth factors, some of which are delivered directly to the GI lumen, as they are swallowed constituents of amniotic fluid, colostrum, and milk. Granulocyte colony-stimulating factor (G-CSF), traditionally known as a granulocytopoietic growth factor, is an example of one such factor. However, it is not clear whether the large amounts of G-CSF that are normally swallowed by the fetus and neonate have systemic effects on circulating neutrophils or local effects in the developing intestine.

Bioavailability of granulocyte colony-stimulating factor administered enterally to suckling mice.

The developing fetal and neonatal gastrointestinal (GI) tract is influenced by many growth factors, including epidermal growth factor (EGF), insulin-like growth factor (IGF), transforming growth factor (TGF), and erythropoietin (Epo). Granulocyte colony-stimulating factor (G-CSF), typically regarded as a hematopoietic growth factor, might also be included because it exists in high concentrations in amniotic fluid, colostrum, and human milk, and because granulocyte CSF receptors (G-CSF-R) are abundantly expressed on the villous enterocytes of the developing intestine. As a first step toward understanding whether the effects of G-CSF on the GI tract were local or systemic, we sought to determine whether recombinant human G-CSF (rhG-CSF) administered enterally to suckling mice, is absorbed into the circulation, and if so, whether the G-CSF-R is essential for this absorption.

Messenger RNA expression of granulocyte colony-stimulating factor receptor isoforms in the fetus.

Granulocyte colony-stimulating factor (G-CSF) is a growth factor known to support the proliferation, differentiation, and survival of cells of the neutrophil lineage. G-CSF affects these cells after binding to its specific receptor, G-CSF-R, which exists in seven isoforms. While information exists about the distribution of these isoforms in hematopoietic cells and placenta, G-CSF-R isoforms on non-hematopoietic fetal tissues have not been described.

Circulating concentrations of chemokines in cord blood, neonates, and adults.

Chemokines are critical for the movement of leukocytes. Chemotaxis is deficient in neonates, particularly those delivered prematurely, and this likely contributes to their increased vulnerability to sepsis. The concentrations of circulating chemokines in neonates have not been reported, nor is it known whether low chemokine concentrations contribute to their defective chemotaxis.