Characterization of endothelin secretion by vascular endothelial cells.
The characterization of mechanisms that regulate ET-LP secretion from bovine adrenal cortical capillary endothelial cells (ACE) in culture was performed by developing radioimmunoassays that distinguish between ET1-21 (AbET1-21) and ET1-39 (AbET1-39). The conditioned media (DMEM) content of ET-like immunoreactivity (ET1-21LI) increased from 50 to 350 pg/ml over a 24 h period. Addition of 10% calf serum or 0.1% BSA enhanced ET1-21LI release 2-3 fold. Authenticity of ET1-21LI was examined using reversed phase liquid chromatography. All ET1-21LI co-eluted with authentic ET-1. Examination of ET1-39IR by liquid chromatography revealed two peaks of immunoreactivity, one co-eluting with authentic ET22-39 and a later running peak co-eluting with authentic ET1-39. Neither ET1-21LI nor ET1-39LI was detected in the extracts of sonicated ACE cells. Treatment of cells with various forms of TGF beta significantly augmented ET1-21LI release. These data suggest that ACE secretion of ET-LP in vitro spontaneously and can be enhanced by TGFss. Since neither ET1-21 LI nor ET1-39 LI was detectable detectable in ACE cells it is unlikely that ET-LP are stored prior to their secretion.
Hexum
T D
TD
Department of Medicine, University of California, San Diego 92103.
Hoeger
C
C
Rivier
J E
JE
Baird
A
A
Brown
M R
MR
D000818:Animals; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D016232:Endothelins; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010455:Peptides / Q000032:analysis / Q000378:metabolism*; D011817:Rabbits; D011863:Radioimmunoassay; D015291:Transforming Growth Factors / Q000494:pharmacology
D016232:Endothelins; D010455:Peptides; D015291:Transforming Growth Factors