A vasoactive peptide, endothelin-3, is produced by and specifically binds to primary astrocytes.
Primary rat astrocytes were found by immunohistochemistry to display positive staining for endothelin-3, located predominantly in the perinuclear area. The ability of these cells to produce and release endothelin-3 was confirmed by a combination of reverse-phase HPLC and radioimmunoassay, specific for endothelin-3, which demonstrated immunoreactive peptide in cellular extracts and astrocyte-conditioned medium. In addition, astrocytes were shown to possess a single class of binding sites for endothelin with comparable high affinity for endothelin-1, -2 and -3. These results suggest that astrocytes, by virtue of their ability to produce and secrete endothelin-3, serve as a potential extravascular source of intracerebral vasoregulation capable of influencing regional cerebral blood flow.
Ehrenreich
H
H
Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892.
Kehrl
J H
JH
Anderson
R W
RW
Rieckmann
P
P
Vitkovic
L
L
Coligan
J E
JE
Fauci
A S
AS
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D002478:Cells, Cultured; D016232:Endothelins / Q000096:biosynthesis / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D007700:Kinetics; D011485:Protein Binding; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000378:metabolism*; D017466:Receptors, Endothelin
D016232:Endothelins; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin