Luteinizing hormone-releasing hormone and neuropeptide Y influence deoxyribonucleic acid replication in three anterior pituitary cell types. Evidence for mediation by growth factors released from gonadotrophs

Tilemans, Diane

doi:10.1210/en.130.2.882

Cited by 43 publications

(26 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several candidate peptides can be put forward. Tilemans et al (41) showed that the development of prolactin-, growth-hormone-and ACTH-containing cells in the anterior pituitary of the rat is modulated by luteinizing hormone-releasing hormone and that the action of this hormone is mediated by speci®c growth factors released from gonadotropes. These speci®c growth factors were not identi®ed in this study.…”

Section: Discussionmentioning

confidence: 99%

Effects of corticotrophin-releasing hormone, vasopressin and insulin-like growth factor-I on proliferation of and adrenocorticotrophic hormone secretion by canine corticotrophic adenoma cells in vitro

Wijk

Rijnberk²,

Croughs³

et al. 1998

European Journal of Endocrinology

View full text Add to dashboard Cite

Extrinsic factors such as hypothalamic hormones or intrapituitary growth factors may stimulate clonal expansion of a genomically altered cell and therefore play a role in pituitary tumorigenesis. Here we report on the effects of the hypophysiotrophic hormones corticotrophin-releasing hormone (CRH) and vasopressin (AVP) and the intrapituitary growth factor insulin-like growth factor-I (IGF-I) on the proliferation of, as measured by the bromodeoxyuridine labelling index, and ACTH secretion by normal canine pituitary cells and corticotrophic adenoma cells of dogs with pituitary-dependent hyperadrenocorticism. The sensitivity to inhibition by cortisol was analysed under various conditions.Under basal conditions, no signi®cant differences were found in the bromodeoxyuridine labelling indices between control cells and tumour cells. CRH, AVP, IGF-I and cortisol had no effect on the proliferation of canine pituitary cells or canine corticotrophic adenoma cells. In contrast with normal pituitary cells, the proliferation of corticotrophic adenoma cells was stimulated by fetal calf serum (FCS). This FCS-induced proliferation was not inhibited by cortisol.The CRH-induced ACTH secretion by corticotrophic adenoma cells was signi®cantly (P < 0.05) lower than that by normal pituitary cells after 4 h incubation with CRH. Incubation with cortisol for 24 h resulted in reduced ACTH secretion under basal and AVP-or IGF-I-stimulated conditions. The relative inhibition was, however, signi®cantly (P < 0.05) lower in ACTH-producing tumour cells than in normal pituitary cells. Cortisol did not inhibit the CRH-induced ACTH secretion in normal pituitary cells after 24 h.In conclusion, canine corticotrophic adenomas are less sensitive to stimulation by CRH and less sensitive to inhibition by glucocorticoids. These tumours have an aberrant sensitivity to a growthpromoting factor present in FCS. This factor may have an important role in the growth promotion of canine corticotrophic tumours. European Journal of Endocrinology 138 309±315

show abstract

Section: Discussionmentioning

confidence: 99%

Effects of corticotrophin-releasing hormone, vasopressin and insulin-like growth factor-I on proliferation of and adrenocorticotrophic hormone secretion by canine corticotrophic adenoma cells in vitro

Wijk

Rijnberk²,

Croughs³

et al. 1998

European Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…Insight into FS cell function had a new launch when, about two decades ago, Denef and co-workers identified FS cells as cells endowed with paracrine regulatory activities. During the search for a paracrine factor involved in lactotrope -gonadotrope communication (48,49), a factor was unexpectedly detected that caused the attenuation of secretion responses to either stimulatory (24) or inhibitory hormones (25) (see Table 1). This attenuating effect was more pronounced in cell aggregates obtained from low-density gradient fractions, in which FS cells (i.e.…”

Section: Fs Cells In Paracrine Communication In the Anterior Pituitarymentioning

confidence: 99%

History and perspectives of pituitary folliculo-stellate cell research

Allaerts¹,

Vankelecom²

2005

eur j endocrinol

157

129

View full text Add to dashboard Cite

Historically, the study of folliculo-stellate (FS) cells of the anterior pituitary dates back to the onset of electron microscopical observation of the pituitary gland. The morphological and electrophysiological characteristics, topographical distribution and contribution to intercellular junctions of these FS cells have been instrumental to the understanding of their putative function. Moreover, many studies have documented the role of FS cells as a source of newly discovered peptides, growth factors and cytokines. Quantitative immunohistochemical observation of FS cells in situ and functional in vitro studies, using either cultured FS cells or cells from an immortalized FS cell line, forwarded the notion of immunophenotypical and functional heterogeneity of the FS cell group. Double immunolabeling with a classical FS cell marker (S-100 protein) and with major histocompatibility complex class II markers characteristic for dendritic cells (DC) have shown a considerable overlap of FS cells with DC. The latter cells are immunocompetent cells belonging to the mononuclear phagocyte system. In this review, the FS cell heterogeneity is discussed with respect to the question of their embryological origin and developmental fate and with respect to the physiological relevance of functionally heterogeneous subpopulations. Recent findings of a myeloid origin of part of the interstitial cells of the anterior pituitary are confronted by other developmental paradigms of pituitary cell differentiation. The possibility that FS cells represent an adult stem cell population of the pituitary is critically examined. Also the physiological role of FS cells in the interferon-g-and nitric oxide-mediated effects on pituitary hormone secretion is discussed. New approaches for the study of this enigmatic cell group using immortalized cell lines and new markers for an hitherto unrecognized pituitary cell population, the so-called 'side population', are evaluated.

show abstract

“…After 5 days in culture, aggregates were treated with rat IFN-␥ (500 U/ml) (courtesy of Prof. P. Van der Meide; ITRI, Rijswijk, Nederland) for 24 hr. Subsequently, they were fixed in Zamboni fluid (4% paraformaldehyde and 15% saturated picric acid solution in 0.1 M phosphate buffer, pH 7.4) for 4 hr, paraffin-embedded, and sectioned as previously described (Tilemans et al 1992;Denef et al 1989).…”

Section: Immunocytochemistry Of Paraffin-embedded Sections From Rat Amentioning

confidence: 99%

“…Immunostaining was performed as reported previously (Tilemans et al 1992;Denef et al 1989). Briefly, permeabilisation by trypsin (0.1% bovine pancreatic trypsin, Type III; Sigma Chemical, St Louis, MO) and incubation with preimmune swine serum (Dako) (1:5 in PBS, pH 7.4) was followed by overnight reaction with the polyclonal rabbit anti-iNOS antiserum (at a dilution of 1:2000 in PBS).…”

Section: Immunocytochemistry Of Paraffin-embedded Sections From Rat Amentioning

confidence: 99%

Inducible Nitric Oxide Synthase in the Anterior Pituitary Gland: Induction by Interferon-γ in a Subpopulation of Folliculostellate Cells and in an Unidentifiable Population of Non-hormone-secreting Cells

Vankelecom

Matthys

Denef

1997

J Histochem Cytochem.

View full text Add to dashboard Cite

SUMMARYIn the context of immune-endocrine relationships, we have previously shown that interferon-␥ (IFN-␥) inhibits hormone secretion in anterior pituitary (AP) cell cultures. The non-hormone-secreting folliculostellate (FS) cells were found to mediate this inhibitory action. Because in the immune system IFN-␥ is a strong stimulator of nitric oxide (NO) release through the induction of NO synthase (NOS), we investigated whether the inducible form of NOS (iNOS) is present in (rat) AP cell cultures, and whether its expression is stimulated by IFN-␥. Immunocytochemistry revealed that under basal in vitro conditions only a very few AP cells contained iNOS. Treatment with IFN-␥ caused a sixfold rise in the number of iNOS-positive cells and augmented the intensity of the staining. The increased number of iNOS-expressing cells was paralleled by elevated production of NO. Some of the iNOSpositive cells extended cytoplasmic processes between hormone-secreting cells, which is a characteristic of FS cells. Immunostaining of FS cell-poor and FS cell-enriched populations (obtained by gradient sedimentation) also suggested the presence of iNOS in a subpopulation of FS cells. By double immunofluorescence techniques we found that about 65% of iNOS-expressing cells were positive for S-100, a marker protein for FS cells. However, around 80% of the S-100-positive cells were not labeled for iNOS. On the other hand, the majority of the S-100-negative iNOS-containing cells could not be further identified by antisera against the classical AP hormones, suggesting the presence of iNOS in a still unidentified non-hormone-secreting cell type of the AP gland. This report is the first to demonstrate the expression of the inducible form of NOS in the AP gland. IFN-␥ upregulates this expression, showing that cytokines may use the same signaling mechanisms in both the immune and the endocrine system. In addition, a putative new function of a subpopulation of FS cells in the paracrine regulation of the AP gland is suggested. by the presence of S-100, a cytoplasmic protein which, at least in rat and human AP, is found exclusively in FS cells (Vankelecom et al. 1993). The functional significance of FS cells is poorly characterized despite their discovery as early as 1953 (Rinehart and Farquhar 1953). Our group provided evidence for a paracrine regulatory role in the AP gland (Denef 1994;Allaerts et al. 1990a). FS cells attenuate the secretory responses of hormone-secreting cells to both stimulatory and inhibitory hypothalamic factors, possibly through the release of (a) paracrine molecule(s) (Denef

show abstract

Luteinizing hormone-releasing hormone and neuropeptide Y influence deoxyribonucleic acid replication in three anterior pituitary cell types. Evidence for mediation by growth factors released from gonadotrophs

Cited by 43 publications

References 0 publications

Effects of corticotrophin-releasing hormone, vasopressin and insulin-like growth factor-I on proliferation of and adrenocorticotrophic hormone secretion by canine corticotrophic adenoma cells in vitro

Effects of corticotrophin-releasing hormone, vasopressin and insulin-like growth factor-I on proliferation of and adrenocorticotrophic hormone secretion by canine corticotrophic adenoma cells in vitro

History and perspectives of pituitary folliculo-stellate cell research

Inducible Nitric Oxide Synthase in the Anterior Pituitary Gland: Induction by Interferon-γ in a Subpopulation of Folliculostellate Cells and in an Unidentifiable Population of Non-hormone-secreting Cells

Contact Info

Product

Resources

About