𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Role of the astrocytic ETB receptor in the regulation of extracellular endothelin-1 during hypoxia

✍ Scribed by Martin Hasselblatt; Piotr Lewczuk; Bernd-Michael Löffler; Heike Kamrowski-Kruck; Nicolas Von Ahsen; Anna-Leena Sirén; Hannelore Ehrenreich

Publisher
John Wiley and Sons
Year
2001
Tongue
English
Weight
267 KB
Volume
34
Category
Article
ISSN
0894-1491

No coin nor oath required. For personal study only.

✦ Synopsis

Astrocytes are known to possess an effective endothelin (ET) eliminatory system which involves astrocytic ET A and ET B receptors and may become particularly relevant under pathophysiological conditions. The present study has therefore been designed to explore the effect of standardized hypoxia on extracellular concentrations of endothelin-1 (ET-1) and on endothelin-converting enzyme (ECE) activity in primary rat astrocytes genetically (sl/sl) or experimentally (dexamethasone) deficient in ET B receptors. The results revealed (1) a hypoxia-mediated decrease of extracellular ET-1 in wildtype astrocytes (ϩ/ϩ) that was not observed in ET B -deficient (sl/sl) cultures;

(2) an ET receptor antagonist-induced increase in ET-1 in the media of both genotypes with further elevation upon hypoxia in ϩ/ϩ cultures only; (3) augmentation of the dexamethasone-induced increase in extracellular ET-1 by hypoxia in ϩ/ϩ, but not in sl/sl cultures; (4) synergistic reduction of ET B gene transcription by hypoxia and dexamethasone; and (5) significant increases in endothelin-converting enzyme activity in the presence of hypoxia. To conclude, hypoxia stimulates astrocytic release of mature ET-1. This stimulation is (over)compensated for by increased ET-1 binding to functional ET B receptors. ET B deficiency, whether genetic or experimentally induced, impairs elimination of extracellular ET-1.

📜 SIMILAR VOLUMES

The role of extracellular signal-regulat
The role of extracellular signal-regulated protein kinase in transcriptional regulation of the hypoxia marker carbonic anhydrase IX
✍ Stefan Kaluz; Milota Kaluzová; Eric J. Stanbridge 📂 Article 📅 2005 🏛 John Wiley and Sons 🌐 English ⚖ 266 KB

In the present study, we investigated the role of the extracellular signal-regulated protein kinase (ERK) in regulation of the hypoxia marker, carbonic anhydrase IX (CAIX). U0126, a specific inhibitor of MEK1/2, downregulated CAIX expression induced by true hypoxia and cell density. CA9 promoter act

Role of the low-density lipoprotein rece
Role of the low-density lipoprotein receptor-related protein-1 in regulation of chondrocyte differentiation
✍ Kazumi Kawata; Satoshi Kubota; Takanori Eguchi; Norifumi H. Moritani; Tsuyoshi S 📂 Article 📅 2010 🏛 John Wiley and Sons 🌐 English ⚖ 427 KB

## Abstract The low‐density lipoprotein receptor‐related protein 1 (LRP1) is known as an endocytic and signal transmission receptor. We formerly reported the gene expression and the localization of LRP1 in cartilage tissue and chondrocytes, but its roles in the differentiation of chondrocytes remai

NERF2, a member of the Ets family of tra
NERF2, a member of the Ets family of transcription factors, is increased in response to hypoxia and angiopoietin-1: A potential mechanism for Tie2 regulation during hypoxia
✍ Rial A. Christensen; Koshi Fujikawa; Rebecca Madore; Peter Oettgen; Lyuba Vartic 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 246 KB 👁 1 views

## Abstract Vascular endothelial growth factor (VEGF) and angiopoietins regulate endothelial cell survival and migration and are essential for angiogenesis. Considerable progress has been made towards understanding hypoxia‐mediated regulation of VEGF and its receptors. In contrast, little is known

Prostaglandin F2α induces the normoxic a
Prostaglandin F2α induces the normoxic activation of the hypoxia-inducible factor-1 transcription factor in differentiating 3T3-L1 preadipocytes: Potential role in the regulation of adipogenesis
✍ Li Liu; Neil A. Clipstone 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 228 KB

## Abstract Prostaglandin F2α (PGF2α) is a potent paracrine inhibitor of adipocyte differentiation. Here we show that treatment of differentiating 3T3‐L1 preadipocytes with PGF2α induces the expression of DEC1, a transcriptional repressor that has previously been implicated in the inhibition of adi

Role of CB1 and CB2 receptors in the inh
Role of CB1 and CB2 receptors in the inhibitory effects of cannabinoids on lipopolysaccharide-induced nitric oxide release in astrocyte cultures
✍ Francisco Molina-Holgado; Eduardo Molina-Holgado; Carmen Guaza; Nancy J. Rothwel 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 276 KB 👁 1 views

## Abstract The purpose of this study was to investigate the role of the central cannabinoid receptor (CB~1~) in mediating the actions of the endogenous cannabinoid agonist anandamide and the synthetic cannabinoid CP‐55940. Activation of primary mouse astrocyte cultures by exposure to bacterial lip