Insulin-like growth factor 1 (IGF-1) is involved in the regulation of brain development and has been suggested as an autocrine stimulator of brain tumor cell proliferation. This study demonstrates the expression of IGF-1 in tumor tissue from human gliomas and one esthesioneuroblastoma. Using immunohistochemistry, expression of an IGF-1-like peptide was localized in tumor cells of 6 of the 9 gli...

Addition of insulin-like growth factor-1 (IGF-1) to culture medium increases the proportion of bovine embryos that develop to the blastocyst stage and increases embryo survival following transfer to heat-stressed, lactating dairy cows. The objective of the present study was to determine molecular and cellular correlates of these actions of IGF-1. Embryos were produced in vitro and cultured for ...

We have compared the influence of insulin-like growth factor 1 (IGF-1) on pituitary gene expression in the rat cell lines GH4C1 and GH3. Incubation with IGF-1 increased PRL messenger RNA (mRNA) levels in GH4C1 cells by 4- to 5-fold but decreased the levels of PRL transcripts in GH3 cells. In addition, the levels of GH-mRNA that were not affected by IGF-1 in GH4C1 cells were significantly inhibi...

The human insulin-like growth factor-1 (IGF-1) gene gives rise to multiple, heterogeneous mRNA transcripts through a combination of multiple transcription initiation sites, alternative splicing and different polyadenylation signals. These IGF-1 mRNA transcripts code different isoforms of the precursor peptide of IGF-1 (IGF-1Ea, IGF-1Eb and IGF-1Ec or MGF in human skeletal muscle), which also un...

We have previously demonstrated specific insulin-like growth factor I (IGF I) mRNA transcripts in cultured endothelial and vascular smooth muscle cells and postulated an important role for IGF I in blood vessel growth responses. The purpose of this study was to characterize IGF I gene expression in a model of aortic coarctation hypertension in the rat. This high-renin model of hypertension is a...

insulin – like growth factor – i (igf-1) plays a role in the skeletal muscle in the development, growth, repair, and maintenance of the tissues in an autocrine / paracrine as well as endocrine fashion. the aim of the present study was to investigate the response of growth factors to two different training methods. 14 male volunteers were selected and divided randomly into two groups. group a (p...

10- to 12-week-old human embryonic eye globes were microdissected so that a passage was opened between the outer environment and the anterior chamber which rendered free access of tissue culture medium to the endothelial cell monolayer. The dissected eye globes were maintained in organ culture for 24 h in the continuous presence of tritiated thymidine. Cross sections were cut through the whole ...

Insulin-like growth factors (IGF) I and II are polypeptides with both growth-promoting and insulin-like metabolic effects. The developmentally specific expression of IGF I and II in the nervous system implies a role for these growth factors in neuronal growth and differentiation. In the present study, we analyzed IGF and IGF receptor mRNA transcripts from two related human neuroblastoma cell li...

Insulin-like growth factor-I (IGF-I) has been implicated in the pathogenesis of prostate cancer (PCa), since it plays a key role in cell proliferation, differentiation, and apoptosis. The IGF-I actions are mediated mainly via its binding to the type I IGF receptor (IGF-IR), however IGF-I signaling via insulin receptor (IR) and hybrid IGF-I/IR is also evident. Different IGF-I mRNA splice variant...

The rat insulin-like growth factor II (IGF-II) gene, encoding a fetal somatomedin, expresses a family of transcripts in embryonic/fetal tissues, and also in the adult choroid plexus and the leptomeninges. We have localized IGF-II gene transcripts in sections of rat embryos of embryonic days 10-16 by performing in situ hybridization. These transcripts are present in the head mesenchyme, formed f...