These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Endothelins activate Na+/H+ exchange in brain capillary endothelial cells via a high affinity endothelin-3 receptor that is not coupled to phospholipase C.
    Author: Vigne P, Ladoux A, Frelin C.
    Journal: J Biol Chem; 1991 Mar 25; 266(9):5925-8. PubMed ID: 1848560.
    Abstract:
    Endothelial cells from brain microvessels (BCEC) express high affinity receptor sites for endothelin-1 that recognize endothelin-3 with a low affinity (Vigne, P., Marsault, R., Breittmayer, J.P. & Frelin, C. (1990) Biochem. J. 266, 415-420). Binding experiments using 125I-endothelin-3 showed the presence in BCEC of a new class of receptor sites that had a high affinity for endothelin-3 (Kd = 0.8 nM), endothelin-1 (Kd = 0.8 nM), and sarafotoxin S6b (Kd = 0.3 nM). Endothelins activated phospholipase C in BCEC and produced transient increases in intracellular Ca2+ with properties of a low affinity endothelin-3 receptor. Endothelins also increased 22Na+ uptake via the Na+/H+ antiporter in BCEC. Concentrations for half-maximum activation (endothelin-1, 0.5 nM; sarafotoxin S6b, 1 nM; endothelin-3, 2 nM) were close to the Kd values determined in 125I-endothelin-3-binding experiments. The action of endothelins on Na+/H+ exchange was not mimicked by phorbol myristate acetate, it was not reversed by staurosporine, and it did not correlate with the phosphorylation of the 80-kDa protein. These results indicated that the action of endothelins on Na+/H+ exchange did not involve protein kinase C. It is concluded that BCEC coexpress two types of functional receptor sites for endothelins: (i) a high affinity endothelin-1, low affinity endothelin-3 receptor that is coupled to phospholipase C and to intracellular Ca2+ mobilization, and (ii) a high affinity endothelin-1, high affinity endothelin-3 receptor that controls Na+/H+ exchange activity via a protein kinase C-independent mechanism.
    [Abstract] [Full Text] [Related] [New Search]